Top 25 social networking sites according to compete.com:

1. facebook.com
2. myspace.com
3. twitter.com
4. flixster.com
5. linkedin.com
6. tagged.com
7. classmates.com
8. myyearbook.com
9. livejournal.com
10. imeem.com
11. reunion.com
12. ning.com
13. blackplanet.com
14. bebo.com
15. hi5.com
16. yuku.com
17. cafemom.com
18. friendster.com
19. xanga.com
20. 360.yahoo.com
21. orkut.com
22. urbanchat.com
23. fubar.com
24. asiantown.net
25. tickle.com