I am a first time iPhone buyer although I am a 20 year Apple user with about a dozen of their products.
I have two friends who also bought the iPhone 4. All are previous Mac users. I have 4 co-workers who bought the iPhone 4, none of which uses a Mac as a computer. For one of them it was his first Apple product.
I do not doubt the problems but none of the people who bought the phone that I know has problems.
The phone can be returned.
Returning a phone used to be easy, but in this case, with the microSIM, you’re screwed and can’t go back to your old phone. I’m guessing AT&T would probably reactivate the old one if I asked, but I could see that taking some time and the aggravation of listening to them pretend that such a thing has never happened before.
I’m definitely worried about it. My iPhone 4 will arrive tomorrow and I’m hoping I can check it out well enough before activating the SIM to make sure it’s in full working condition.