Unless you've been living under a rock lately, you've gotten an earful about the National Security Administration's efforts to monitor your phone calls and online activity. Sure, that's scary stuff, but it's only one piece of the privacy puzzle. What about all the other organizations you're voluntarily giving information to? Just about everywhere you go online, you're leaving a digital footprint and odds are you have no idea who's seeing it.

So, who exactly has access to the personal information you put online?

To answer that question, NPR investigated one of the greatest sources of personal data on the Web: online dating sites. Most users don't hesitate to fill out the lengthy questionnaires on sites like Match.com because they believe it's the best way to find a compatible partner. But when NPR sat down with Ashkan Soltani, a digital privacy specialist who used to work at the Federal Trade Commission, he showed exactly how unprivate personal information can be.

Soltani set up a fake account on OkCupid to demonstrate how private companies track what users are doing online. He selected the "Often" options under the questions about drinking and drug use, then launched two software programs - Collusion and MITM Proxy - to get a look at what goes on behind-the-scenes.

The Collision program revealed that almost 50 companies were tracking Soltani's computer as he browsed OkCupid, most of which were either advertising firms or companies that collect data to sell to ad firms. The MITM Proxy program exposed the kind of information those companies were receiving from OkCupid. Some got basic data, like age and gender, but others obtained much more personal details. In fact, least one learned that Soltani uses drugs "often."

Of course, it's not just OkCupid that collects personal data, and every online dating site has an explanation for why they do it. Data collecting, they argue, allows them to personalize their service in order to improve user experience. As you search for dates online, your dating site gets a better idea of the kind person you're looking for. The site becomes "smarter," and its matching algorithm becomes better at refining your results.

To some, it's creepy. To others, it's helpful. What is clear is this: there isn't much that can be done about it, unless you choose the non-option of staying off the Internet completely. All that's left is to think carefully about what data you choose to share, and to remember that private information is rarely private online.

A new app that has taken the dating world by storm is Tinder, a modern version of the game "hot or not." With Tinder, users can view the photos of other users along with basic information, and make a decision as to whether or not they want to meet. Swipe left to say no, swipe right to say yes. If you both say yes, you can start chatting and potentially meet in real life.

It's a different kind of experience from traditional dating sites, which makes it appealing to many users. It is easier to set up and easier to meet people quickly, rather than with online dating sites that require answering a questionnaire, profile description, and emails back and forth. With Tinder, you can join and meet someone instantly.

But who is using it? Are men more interested in Tinder because of its hook-up potential? Not really. Forty-five percent of Tinder users are female, and they are actively participating. Most of the users also skew on the young side, which isn't surprising. It is less intimidating to use Tinder than to market yourself on an online dating site, which could seem like more of a commitment for someone who is twenty-one and not really looking for a committed relationship.

So Tinder might be easy to use, but how are people really using it? Is it basically a hook-up app? According to most reports, yes. After all, Tinder was marketed to those people who are looking to meet other singles close by quickly, which feeds into the hook-up culture. But according to company executives and a few media members who have tried it, people can unexpectedly find love, too.

Like other online dating sites, you don't always know who it is you're meeting, and people definitely flake and don't show up, whether you meet via Match.com or an app like Tinder. It seems bad behavior will exist no matter what the platform you use to meet people.

So what does this mean? Traditional online dating isn't going away anytime soon. There are many people interested in long-term relationships, who prefer reading profile descriptions, emailing and a phone call before meeting someone in person.

But if you're out on a Friday night with your friends and you're looking for some excitement? Tinder might be a good way to socialize. Think about it this way. You look at people in a bar and decide who you want to approach. The only difference with Tinder is that their faces are on a screen.

There is a murky time in almost every relationship where you wonder, "are we still just dating, or are we officially a couple?" And while you might want to know where you stand, it can be difficult to bring it up in conversation. After all, things have been moving along so well. Why ruin it with such a serious topic?

But then again, you don't want to waste time. You want to know where the relationship is headed.

So, how do you judge for yourself? How long do you date each other before you have the conversation about making it exclusive?

A recent poll conducted by DatingSitesReviews.com found that most people (54%) consider how long you've been dating the most important factor in determining your relationship status. In other words, the longer you've been dating, the more you can consider yourself an item. The majority of respondents (26%) felt that if you were dating for more than two months, you were in an official relationship. Nineteen percent felt that dating one to two months granted you the right to call it an exclusive relationship. Only 9% felt that two to four weeks constituted some kind of commitment.

Another important factor besides how long you've been dating: saying those magical three words: "I love you." Nineteen percent of respondents felt that when you said these words to each other, your relationship was official.

One interesting finding was that people don't necessarily view sexual activity while dating as a casual thing. Fifteen percent of respondents felt that a relationship was official once they'd had sex. Nine percent felt a relationship turned serious when you went away on a trip together.

Surprisingly, a traditional gage like meeting your date's parents didn't really factor in to most people's opinion of when you become a couple. Only one percent felt that this was proof that your relationship was official.

And for those who date a bit more casually, only one percent felt that the defining mark of an "official relationship" was when you move in together. So, don't keep dating lots of people until you find someone you can share a bathroom with - most of the men or women you date will think you're an item well before that point.

Bottom line: most people felt that the length of time you've been dating is the gage by which to determine whether or not you're in a relationship. So if you've been dating someone for a while without discussing what you both want, then you might want to talk sooner rather than later.

A few years ago, Match.com became a household name when it comes to online dating. Now that mobile apps like Tinder have gained popularity and people are looking to newer and niche online dating sites like JDate or How About We, people are starting to see what else is out there.

In fact, social media, and Facebook in particular, are becoming players in the game. While traditional sites rely on new sign-ups and static searches, social media-friendly dating sites and apps pull information from a vast pool of active Facebook profiles and introduce you to friends of friends in your network. This has become a big draw for people, because most singles feel more comfortable meeting someone new if they have a friend in common. This is especially true for women, who are sometimes skeptical of the safety of online dating.

According to an article in Wall Street Cheat Sheet, entrepreneurs are just beginning to understand the importance of utilizing social media in industries like online dating, which could mean big revenues in the future. LinkedIn has gained traction in the social media space because the platform focuses solely on job seekers and networkers looking for career opportunities. There is a sense of trust when someone comes recommended for a job by a mutual friend or co-worker, so companies are looking to the service to attract new employees. So why not apply the same principal to those looking for a date?

eHarmony notified us earlier today that they are currently having a free communication event. It starts today and runs for 5 days and ends Monday November 25th just before midnight (PST).

Free communication on eHarmony allows new and existing members to communicate not only by the guide communication process but through email as well. When you join during this promotion you will not only be able to create a profile and take the eHarmony famous matching questionnaire but you will be able to communicate with any matches you will receive in the next 5 days. The ideal time to join is now since it will give you 5 full days to try out the service to see if it is the right fit for you. Singles interested in finding a long-term relationships and who are willing to make a time commitment in not only filling out the questionnaire but to answer questions posed by your matches will get the most out of the eHarmony service. No credit card is required to join. The only thing not included during the free weekends is photos, secure call and skip to email.

The last free eHarmony communication weekend was at the beginning of this month (see Story). For more on this long-term matchmaking service please read our eHarmony.com review.

Women can be picky daters. At least, that's the stereotype. We like our men to be incredibly hot, smart, successful, and charming, and we aren't willing to settle for anything less, right ladies?

Well, maybe that holds true for women in some cities, but not others.

According to data released from dating website AreYouInterested.com, women in Brooklyn are the pickiest daters in America (coming in ahead of Los Angeles and Manhattan). The website compiled this information based on 453,000 interactions of women ages 18 and up, noting that Brooklyn residents are the least likely to reply to messages from potential dates. Men would have more luck in Jersey City, New Jersey.

Behind Brooklyn, Detroit, Minneapolis, Cincinnati and Los Angeles also ranked highest for the pickiest daters.

But perhaps creativity has something to do with response rates. AYI.com also found that emails engaging the respondent ("where are you from?") worked much better than emails just saying "hi," or "what's up?" which fell flat.

Other interesting findings:

• Women are 71% more likely to respond to someone if they have a mutual friend on Facebook.
• Women are three times more likely to respond to a younger man than men are to respond to a younger woman. It seems cougars are in among AYI.com members!

The cities where women are most likely to get in touch after a potential date has reached out include Miami, St Louis, Las Vegas and Portland, Oregon. So guys, on your next Vegas trip you might want to consider moving permanently.

AYI.com has an interesting base of users though - it's not strictly an online dating site, but identifies itself as more of a social discovery site. Members don't only join for dating purposes, but also to form friendships. Social discovery sites provide a place where people can meet and socialize online - to make friends, play video games, exchange music, or a number of different things - not just to date. Which means users who join stay around longer, even after they meet a significant other.

So are women picky about their friendships, too?

According to its website, AYI.com has more than 70 million installed users and over 3 million Facebook fans. It offers an integrated Facebook app, iPhone app, Android app and website, and works by connecting members to each other based on mutual Facebook friends and interests.

The company is owned by SNAP Interactive and you can find more details on them by reading our review of Are You Interested.