list of social networking sites

Check here for all the latest, I will repost as I find them:

Name	Description/Focus
43 Things	Tagging
Advogato	Free Software and Open Source developers
aSmallWorld	European jet set and social elite
BlackPlanet.com	African-Americans
Bebo	Schools and colleges
Blue Dot	Link sharing
Broadcaster.com	Video sharing and webcam chat
Blurty	Blogs, based on LiveJournal
Bolt	General (music and video)
CarDomain	Car enthusiasts
Care2	Green living and activism
Classmates.com	School, college, work and the military
Consumating	"Consumeetings"
Couchsurfing	"Couchsurfing"
Cyworld	Young South Koreans
Dandelife	Collective narratives or "shared biographies"
DeadJournal	"Dark" blogs, based on LiveJournal
Dodgeball.com	Mobile location-based service, owned by Google
DontStayIn	Clubbing (primarily UK)
Doostang	Careers
Ecademy	Business
eSPIN	Teen Dating
Facebook	College/High School students
Faceparty	British teens and 20-somethings
Flirtomatic	Flirting/Dating
Flickr	Photo sharing
Fotki	Photo sharing
Friends Reunited	School, college, work, sport and streets
Friendster	General
Frühstückstreff	General
FUPEI	General (Photo, Video, Music, Games, Event, and Chat Room)
Gaia Online	Anime and Games
Gazzag	General
Geni.com	Families, genealogy
GoPets	Virtual pets
Graduates.com	School, college, and work
GreatestJournal	Blogs, based on LiveJournal
Grono.net	Poland
Hi5	General
Hyves	General; focus on students and Dutch speakers
imeem	Instant messaging
IMVU	3D chat software
IRC-Galleria	Finland
iWiW	Hungary
Joga Bonito	Football (soccer)
JuiceCaster	General
Last.fm	Music
LinkedIn	Business
LiveJournal	Blogging
LunarStorm	Sweden
MEETin	General
Meetup.com	General
MiGente.com	Latinos
Mixi	Japan
MOG	Music
Multiply	"Real world" relationships
MySpace	General
myYearbook	General
Netlog	European young adults (14-24). Formerly known as Facebox.
Nexopia	Canada
orkut	Owned by Google
Passado	General
Phrasebase	Foreign Languages (education)
Piczo	Teenagers, Canadians, photo sharing
Playahead	Swedish teenagers
ProfileHeaven	British teens
RateItAll	Consumer ratings + social networking
Reunion.com	Locating friends and family, keeping in touch
Rimzu	Sociometric rankings
Ringo.com	General
Ryze	Business
Sconex	American high schools
Sportsvite	Recreational Sports
Studivz	University students, mostly in the German-speaking countries
Stumbleupon	Websurfing
TagWorld	General (tagging)
TakingITGlobal	Social action
The Student Center	Teens and colleges
Threadless	Custom T-shirts
Travellerspoint	Travel
Tribe.net	General
Twitter	Update friends with your status through SMS, IM, web interfaces
Vampire Freaks	Gothic industrial culture
Vox	Blogging
WAYN	Travel & Lifestyle
WebBiographies	Genealogy & Biography
Windows Live Spaces	Blogging (formerly MSN Spaces)
Xanga	Blogs and "metro" areas
XING	Business
Xuqa	Colleges
Yahoo! 360°	Linked to Yahoo! IDs
Yelp	United States adults
Zaadz	Social consciousness