I'll be visiting Australia in July, and was wondering... Two carriers there are saying that they'll be selling an unlocked iPhone 3G. what if I bought one there, and brought it home to the U.S.? I'd still have to go with AT&T (right? -- since they're the only one with a GSM network that would accept new activations); but, would I have to get the 2-year plan? Would I be able to go pre-paid? would they insist that I get one of their announced iPhone 3G plans? (After all, I'd have a completely legal, unlocked iPhone 3G...) Just curious... OWF.