You speak as if Apple is in control of the ringtone situation. It will be the recording companies who tell Apple what they can and cannot do with their artists' music. Considering that ringtones have become a billion dollar business, I doubt they will allow Apple to do anything that jeopardizes this form of income.

As for selling ringtones, if there isn't a way to purchase them through Cingular as you would a normal handset then the service will have to come from iTunes. Apple would probably make the same small amount of pennies on the sale of a ringtone that they do a song purchased from iTunes.

Whatever you can do with your current handset in terms of chopping a song and loading it onto your phone will likely be allowed on the iPhone. We have no choice but to assume that. Perhaps there will be new software that allows you to cut up songs more easily but ringtones themselves are not the property of Apple.