I have the BlackBerry 8800 from AT&T, and I was thinking about upgrading to the BlackBerry 8310. I was wondering, if I buy it from AT&T's website, can I just insert my SIM card for it to work? I have an unlimited data plan and unlimited text messaging, will it all transfer over to the new BB??
yes, it will work and your plan moves with your SIM, not the device. This goes for any unlocked GSM device that works here in the states. the SIM identifies you to the network. to transfer contacts and apps, youw ill need to use the switch device wizard located in Device Manager