I looked through Alexa's Top 100 English site list, to see how many (and which) were in the loosely defined area of social media/user-generated content. (I would have done the Global 500 list, but there were too many I couldn't decipher.)
With the caveats that Alexa's data is not comprehensive—and even if they had perfect stats, "Alexa Rank" is still just one definition of popularity (a combination of reach and pageviews)—here's the 10 most popular social media sites (with corresponding Alexa 100 rank):
1. MySpace (8)
2. Blogger (16)
3. Xanga (20)
4. Hi5 (31)
5. Orkut (33)
6. Thefacebook (41)
7. Friendster (46)
8. Flickr (51)
9. LiveJournal (NA)
10. Photobucket (77)
Interesting that the most popular for users aren't necessarily the most talked-about among the digerati. Speaking of which, if MSN Spaces had its own domain, I'm sure it'd be on the list, quite high. There might be other sites like that. Also, LJ wasn't actually in Alexa's top 100 list; I'm not sure why.
Also interesting: None of the sites are less than a year old; three (Blogger, Xanga, LiveJournal) are more than five years old; and Friendster is the only one between two and five years.
With the caveats that Alexa's data is not comprehensive—and even if they had perfect stats, "Alexa Rank" is still just one definition of popularity (a combination of reach and pageviews)—here's the 10 most popular social media sites (with corresponding Alexa 100 rank):
1. MySpace (8)
2. Blogger (16)
3. Xanga (20)
4. Hi5 (31)
5. Orkut (33)
6. Thefacebook (41)
7. Friendster (46)
8. Flickr (51)
9. LiveJournal (NA)
10. Photobucket (77)
Interesting that the most popular for users aren't necessarily the most talked-about among the digerati. Speaking of which, if MSN Spaces had its own domain, I'm sure it'd be on the list, quite high. There might be other sites like that. Also, LJ wasn't actually in Alexa's top 100 list; I'm not sure why.
Also interesting: None of the sites are less than a year old; three (Blogger, Xanga, LiveJournal) are more than five years old; and Friendster is the only one between two and five years.