Facebook Is the social networking site for marketing.
I think Facebook is the most powerful social network today.
Her there are many great social networks like Twitter, Digg, MySpace, LinkedIn, etc...
Facebook is definitely #1. Also like Identi.ca because you can generate a few high pr backlinks while networking with others.
Twitter and Orkut.
rest of all are useless. imo.
facebook and twitter, Digg also not bad. In Russia we have vkontakte, its also very popular here more than facebook
Facebook and Twitter has become really big. It says Facebook get more traffic than Google it self ! Other social networking sites like My Space and Hi slowly dying, it seems.
FACEBOOK is the best at this moment.. with 500 million user and it increases each day, you just need to know how to optimize it (such as fan page, like button, and so on)
Facebook is the best and most popular till now.
1. facebook
2.twitter
3.digg
4. stubleupon
5.reddit
6- infintey not worth the time
most are freeeeeeeeeeeee