When you have no other choice but to go with AT&T wireless service because you have an unlocked iPhone from India, be very aware of which type of AT&T store you go, because yes, there IS a difference between the authorized dealer and the service center.
When you attempt to sync your iPhone with your iMac that you finally set up in your rental home, be aware that your unlocked phone will lock up, and you won't be able to use it anymore. Remember this dingbat, a locked phone is a locked phone ... and only works in the country in which it was purchased.
You'll thank yourself later that you went to the Apple store immediately in your gnarly clothes with smudged mascara, ratty hair, and 3 starving kids because they wait on you quickly in hopes that you'll soon leave their store. And though they really want to help you but can't due to proprietary software, they will tell you under their breath that their good friend Mr. Google can help fix the problem.
You may ponder for a brief moment or two about spending your few available minutes at home trying to figure out exactly how your new friend Mr. Google may be able to fix said problem. Or you'll quickly come to your senses and just ask how much money it costs to upgrade to the new iPhone 4. Because that's what you really want anyway.
You'll then drive to an AT&T service center to beg and plead with them to give you the upgraded phone even though you've been told you're not eligible for another 13 months ... only to discover that you ARE eligible ... except the AT&T authorized dealer signed you up incorrectly. When you come with your own hardware, you are able to sign up for a month-to-month contract, and aren't required to have a two-year contract.
So you'll then drive your unbelievably happy a** back to the original place you signed up for your service (because the service center has NO access to the authorized dealer's original information) and have an utter and complete meltdown in their store. You'll demand they change your contract. You'll demand it's taken care of immediately. You'll demand they give you a loaner phone while the contract takes 48-72 hour to change.
And you'll let your kids play with every single phone, case, and accessory in the place while they're fixing the problem. Then you'll feed them ice cream for lunch.