Well, my purpose is to learn english...
Why of course, the sole purpose of the Internet is to cater to your needs!
4-ch should be more active. But I have trouble thinking of good topics of discussion, so I don't make any threads. I should be doing more.
If you want to learn English join an IRC or play English MMORPGs.
There are plenty of online resources you can use to learn English. And even if you don't use any of them, you can still immerse yourself in an English environment and absorb some indirectly. Try these:
http://www.hulu.com
http://www.bbc.co.uk/worldservice/learningenglish/
http://www.antimoon.com
I have a nagging suspicion that this thread belongs in /language/.