Submitting articles or publishing blog posts on these top web 2.0 websites is very good SEO for blogs and it is the best resources on the web for getting Dofollow backlinks for free.
PR 9 web 2.0 sites
1. Blogger.com
2. wordpress.com
3. bloglines.com
4. Sites.google.com
PR 8 web 2.0 sites
5. Weebly.com
6. livejournal.com
7. tumblr.com
8. scribd.com
9. groups.google.com
10. my.opera.com
11. angelfire.com
PR 7 web 2.0 sites
12. squidoo.com
13. tripod.lycos.com
14. wikispaces.com
15. bravenet.com
16. yola.com
17. jimdo.com
18. storify.com
19. webnode.com
20. zoho.com
21. wikidot.com
22. webs.com
23. quizilla.teennick.com
1. Blogger.com
2. wordpress.com
3. bloglines.com
4. Sites.google.com
PR 8 web 2.0 sites
5. Weebly.com
6. livejournal.com
7. tumblr.com
8. scribd.com
9. groups.google.com
10. my.opera.com
11. angelfire.com
PR 7 web 2.0 sites
12. squidoo.com
13. tripod.lycos.com
14. wikispaces.com
15. bravenet.com
16. yola.com
17. jimdo.com
18. storify.com
19. webnode.com
20. zoho.com
21. wikidot.com
22. webs.com
23. quizilla.teennick.com
