According to the WSJ's sources, Cingular is going to be the official provider for Apple's iPhone/ApplePhone/WhateverPhone in the US. The Apple phone was originally speculated to be both GSM and CDMA, but apparently, it'll only(?) be GSM for Cingular. On the bright side, you can most likely take it onto T-Mobile without too much effort.
However, being on Cingular can possibly mean the iPhone will sport HSDPA, which may also mean the Apple Phone will use HSDPA for video calling (iChat Mobile?) and high speed data. Of course, we pulled that last part out of our CES-sweat-stained ass just now, but it's possible. We'll find out tomorrow.