I know Cingular is saying data rates for the iPhone will be detailed later, but what are Cingular's current data rates?
The root cause here may be data pricing. Apple would prefer Cingular to bill the device as a consumer device with $19.99/month data instead of the $44.99/month price for data-centric devices. Most data-centric devices are considered as such because they run native code, such as Palm OS or Windows Mobile.
Symbian devices however are treated as consumer devices... giving Apple potential wiggle-room to run native OSX-condensed applications on the device without digging into users for data charges.