I kind of figured this would happen with the iPad. All the hype about unlimited 3G connections. The problem is... no apps are going to work over 3G that use any vast amount of bandwidth. I was hoping to get a 3G iPad, I have a WiFi now. I was going to get the unlimited plan and basically use the iPad as a MBP light.
I can tell you this with almost certainty... you will *never* see iPhone tethering now. AT&T probably was close, but once the iPad was a realization... you won't see it. AT&T would rather you have two subscriptions.
Please Verizon.... please Apple. Give us alternatives, if not for just competition with iPhone plan pricing.
AT&T has over 14,000 hot spot zones in their network for Wifi.
http://www.att.com/gen/general?pid=13540
Other than being stuck in a Park or off a highway I sure as hell don't expect anyone driving and using their iPad at the same time, but someone will eventually do it.
I'd never bother with the 3G model. Wifi for me all the way.
I've got a phone for 3G.