Twitter and FourSquare were first introduced at South By Southwest Interactive and have taken off in the social media sphere. What's going to be the big new thing to come out of South By Southwest Interactive this year? The event kicked off on Friday, marking the start of a week-long conference for social media entrepreneurs and techies to introduce their products and make business deals. Over the past few years, SXSW has become the venue to unveil apps that and software that forever change the social media market. 

In today’s world, it’s not unusual to wake up alone, drive to work alone, and eat our meals alone. It’s expected that most of our communicating will take place through machines, rather than face to face. And it’s not unusual for us to develop relationships with those machines, whether they’re our cell phones or GPS devices. But what does all this isolation do to us? And does technology make our isolation better or worse?

On Wednesday, we discussed a new iPhone app which helps Catholic users prepare for the act of confession. To Patrick Leinen, creator of The Confession App, the use of interactive media is a natural and necessary evolution for religions that hope to keep up the pace with a world that rapidly embraces new technology. 

But how about Twitter, Facebook and MySpace; how do these social networks fare in the religious experience of the 21^st Century?

For an MIT professor, Sherry Turkle has a contrarian take on technology: Instead of bringing us together, she says it's actually making us more distant. In a new book called "Alone Together: Why We Expect more from Technology and Less from Each Other," she argues that the kind of relationships we build using our new ways of communicating affects our understanding of intimacy and community — for the worse.

We've been asking you: Has technology ever made you feel more distant? How so?

Here's what you told us by text message (text the word START to 69866 to get in on the conversation):

Goldman Sachs and a Russian investor have invested $500 million in Facebook, raising the company's total value to some $50 billion. According to The New York Times, the deal involves special allowances for Goldman's premier players to invest in the company. The latest deal has spurred more interest from the S.E.C., and may trigger increased pressure on companies like Facebook and Twitter to go public. We're joined by Denis Howlett, writer for the site ZDnet, for more on the story. 

Over the past year, one good way to understand what people in the world are talking about has been to follow the trending topics on Twitter, usually preceded by a hashtag (#). From movies, to revolutions and natural disasters — love it or hate it — Twitter helped the world understand its own conversations in 2010. We take a look at some of the trending topics of the year.  

Relationships drive the social media site Facebook: The friends you let into your network, the groups you seek to join. Relationships are also the crux of Facebook, the movie (aka "The Social Network"). In fact, it's the only part of the movie we're sure is true.

Mark Zuckerberg gets a feature film made about his life and he's not happy with it. I'm not surprised. Apart from his incredible success with Facebook, I'm sure the guy is dealing with all the same issues that most people in their 20s do — conflicting ideas about identity and morality, struggles for true independence, bad dating experiences. Clearly, he's not worried about bounced checks, credit card debt or student loan payments, but I imagine that the rest is the same.

Mark Zuckerberg created the internet phenomenon of a generation, amassed billions of dollars and had a movie made about him ... all by the age of 26. As "Social Network" opens, what would you call the movie about your life at 26?

Here are your suggestions so far.

We have long been aware that there is some connection between having strong friendships and being in good health. But a new study shows that social connections are fundamentally important to our well-being. In fact, not having many strong relationships can be as bad for your health as smoking… and even worse than not exercising. What is a "healthy" social life for you? How many friends and relationships are enough for you?

You've got something you want taken offline: a drunken Facebook photo, an ill-advised blog post about your flirtation with Satanism, a frustrated tweet you wish you could take back. As Facebook passes its 500 millionth user, we take a look at new proposals to reduce the threat that we users of the internet pose to ourselves. 

In Detroit, Mich., a local problem is gaining city-wide attention thanks to the help of some creative reporting and social networking tools. In the city's southwestern neighborhood, known as "Mexicantown," large tractor-trailer trucks take shortcuts down residential blocks, causing property damage and possibly health concerns. 

The Personal Democracy Forum gets under way on Thursday, and many leaders of American politics and social networking will meet to discuss what happens when technology intersects with policy.

Are we sharing too much information on Twitter and Facebook? We're exploring the benefits and the downsides of sharing our personal lives making our private lives public. Help us in an experiment!

Seek out a stranger that you see sharing information on the internet — on Twitter, Facebook, FourSquare — anyone who catches your interest. Don't go stalking though, just reach out and ask them one question for us: What benefit does he or she get from sharing personal information publicly? Tell us what happens and we'll talk about it on the air.

Pro-government marchers flooded Iran's streets yesterday, on the anniversary of Iran's revolution. In fact, pro-government rallies far overshadowed opposition protests. And government supporters in Iran are dominating the online world as well. Social media channels like twitter and youtube had little more than a peep from opposition members. Has Iran's revolutionary spirit seen its end?

Siavash Ardalan is the host for BBC Persian TV's "Your Turn." Gary Sick is an Iran expert at Columbia University.

This afternoon, Joint Chiefs of Staff Chairman Mike Mullen sat down with John Hockenberry to talk about the U.S. military's role in the Haiti relief effort and the fight against terrorism in Afghanistan and Pakistan. But the country's highest ranking military official also told us how he finds the time to send frequent Twitter updates: He credits his wife.

In the aftermath of the earthquake's devastation, residents in Port-Au-Prince had to scramble to help their injured neighbors. Without the help of international aid, they had to make do with basic first aid tools, like alcohol and gauze.

A former guard at Guantanamo Bay has reunited with two of his former prisoners from Britain after he contacted them on Facebook.