Ok, so we know that ATT/Apple are serious about using the IPhone with ATT and an IPhone account (new, 2 years. .forever). We also know that many people have unlocked and some of them are using an old, existing account with their IPhones on ATT (perhaps they had a more attractive plan or didn't want to sign up for two years). So, there has to be a way that ATT can detect the device you are using on their networks (T-Mobile can) and say they decided to look for IPhone usage on non-IPhone accounts. . .and then shut them down (including business accounts) for not following the implied agreement.. .? I think this could happen very soon. I also think that Apple/ATT will have some sort of 'amnesty' for this and unlocked IPhones to enable you to get on the straight and narrow.