>>1. The Community
2) Accurate Answers
3) High Traffic
4) chat (very useful for the study group) *** Does this get included as part of the community
5) PUTM Features

Check out reason number 4. I think you may be implying this with reason number 1.

Please confirm...

Actually, I meant the availability of the chat room, not the chatters (who are already included in #1. #4 should be "chat room" or "chat system".