Very interesting and legally critical case being considered in the USA at the moment.
Can public websites decide who is and is not a criminal through their terms of service? A brief EFF filed yesterday argues no. http://digg.com/d31UoUE
It's weird i actually see this argument from both sides so i'm not sure which side i support yet, i totally agree failure to comply to TOS is not criminal, but should a website have the right to sue users - I dont think so, the rights to ban user? sure "he who brings the bat and ball to the game decides when the game ends", so basically, websites have the right to delete your account and ban you but to "take legal action against you", not sure about this.
Will be interesting to see how this one plays out and what it means for third party tools like Power Ventures.