Google suddently blocks my Adsense Account

Out of the blue I got a mail last week that my Addsense account was blocked. I had started earning a decent amount through it lately as my website started getting some popularity. Supposedly this was due to click fraud. This site is running from a year. If I really wanted to indulge into click fraud I would have done this long time ago. I went ahead and filled in their online appeal form to re-instate my account, but there has been no response from Google Adsense.

Its really unprofessional on Goolge's part to block account without giving any explanation or any statistics. I am sure I didn't click my advertises over and over, so I desperately want to know who did and what was done ? However, there is no way to know since Adsense team won't co-operate.

Reading about this issue over the web it seems like there are many many webmasters who have gone through this and have eventually switched to a different ad network. This unprofessionalism is the usual arrogance from Google. I have really no other choice but to switch over to either MSN or Yahoo Publisher Network .