I happened to see the new Apple iPhone on Friday, the owner claimed to have paid over £350 for it and the device cam from the US. Thus, the phone was, of course, unlocked to be used with other networks than the O2.
When I quizzed him about the Apple warning about unlocking the phone, the owner was pretty cool. As far as I can understand, if you do not have the new firmware upgrade, there are no problems.
The phone itself looks pretty slick and well-designed. The whole touch screen capability seems good and the keypad seems good enough. I have been told that the touch screen is only perceptive to the finger movements and it wouldn't work if it is in your pocket.
One point that might potentially put me off is that the fragility of the screen. This is something to be kept an eye on.