Some more are here–
twitter.com
reddit.com
digg.com
propeller.com
faves.com
buzz.yahoo.com
Here is a list, check this out Social Networking Sites
twitter is one of the best site, it may drives some traffic to your site
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Hi
There are plenty of social networking sites are providing excellent features.Apart from facebook and myspace i like bebo,plaxo,linkedIn and naymz are have good stuff.
Well I’m partial to the site I designed;) , but there is a really extensive list of so net sites at wikipedia.
The best social networking site for professionals is Linkedin.
Yes my dear friend
i am here for your help
i would like to suggest more social networking sites like:- twitter, stumbleupon, linkedin, orkut, ibibo, technoraati, digg, furl, etc. To find more click on www.vmoptions.com/social-networking-list.php?sort=prdesc
there are many social networking sites like Bebo , Friendster , hi5, Orkut , PerfSpot ,Yahoo! 360 , Zorpia , Netlog
there are SN site popping up everyday. virtually one for each and everything thing you are into. So i need to ask what are trying to get out of the network?
1.Traffic?
2.Friends?
3.Kill time?
I recommend joining networks that fit into your scope ans sphere or the sphere you want to be a part of. this way it hits home and you can begin a strong network
hey thanks a lot buddy for providing me with such a long quality list.
But now i understand as some of members mentioned that one should not just add people blindly. We should look for those people with whom we share common interest. so thanks all and thanks to forums 
I’d go for Hi5. Lots of people use it. Most of my friends use it, its kinnda simple but works better then myspace if you ask me.
By the way, great idea, my girlfriends haves like 5.000 friends on Hi5, time to use that potential…
twitter is one of the best social networking sites and then bebo,geni,wayn,hi5.
Twitter, myspace and hi5 are the other social networking and communities sites which are popular nowadays.
hello if you are looking for quality social media sites then i suggest you to use the stumble upon. Reddit, yahoo buzz and some other sites. These are effective and will also give you dofollow links!
have you tried PLURK yet?
Easiest way to check top social media sites is to register and join Ping.Fm. You can see there lots of top social media networks. You can also used Ping.Fm in linking top social media websites.
Well if you are looking for good social networks then there are many good networks. I personally feel that stumble upon and Reddit both are good. b2blocal.net is a good site and has the faster indexing speed. Can any one share the list of social networks that allows dofollow links?
hi,
Well as suggested above, there are n number of social networking site,where most popular are : orkut, twitter, linkedIn and many more…
try newsvine and nowpublic, but be aware that this sites are very strict when it comes to submissions.
There are number of Social Networking Websites available. Well here is the link you can find more and find top ten SNSites in 2010
digitalpercept.com/tag/top-10-social-networking-websites-for-2010/