A friend of mine running a board game site (iggamecenter) had the same problems with google add sense. His account was suspended twice, the first time after some mails to google his account got reactivated, the second time he decided the effort is just not worth the income for him. His explanation was the following: If lots of people click on the adds and don't buy anything google might suspect you are generating artificial hits with bots. They never told him why...

Update 4:48pm - I just logged on to Google+ and my profile has been suspended. That is a big pain in the patootie. I think if was that my cover photo had text in it. I changed it and resubmitted. I may have to use another profile. That sucks.

I really had to constrain myself to prevent +1ing this post, ha ha.