Excerpt from ecommerce-guide.com:

As Facebook’s popularity grows so does the number of third-party applications (called apps for short) that people can add to their profile.  Some Facebook revenue-generating apps let sellers advertise their items to Facebook friends and other people who use the application.  These types of buying and selling apps tend to be used less frequently as many people don’t want to sell items to Facebook friends.

Apps that help sellers connect with buyers from outside their own friend list continue to fuel money-making opportunities on Facebook.  Also, if you don’t have your own items to sell, you can still make money on Facebook using third-party apps to generate commission-based sales via referral programs.

Link: http://www.ecommerce-guide.com/solutions/advertising/article.php/3813226

Link: http://www.ecommerce-guide.com/solutions/advertising/article.php/3800976

Link: http://valleywag.gawker.com/5143256/facebook-founders-settle-their-feud

Link: http://adage.com/digital/article?article_id=134062

Link: http://www.techcrunch.com/2009/01/22/facebook-now-nearly-twice-the-size-of-myspace-worldwide/

This is a really interesting article by Erick Schonfeld over at TechCrunch.com. It looks like there is going to be a lot of changes in search, and because of its reach into all aspects of business it is something everyone should be keeping an eye on. http://www.techcrunch.com/2008/12/28/the-future-of-social-search-or-why-google-should-buy-facebook/

Wall Street Journal Article: http://online.wsj.com/article/SB123007984542431845.html