AT&T's iPhone tethering is something near and dear to our heart. In fact, I may or may not be writing this tethered to my iPhone on a train to New York City right now. We know tethering works on AT&T's network because frankly, we've been doing it using only Apple's software since the iPhone 3.0 betas have been out (and before using PDAnet). To stay tethering, all we've had to do is not update to 3.1 - which isn't that easy.
Tethering is really handy when travelling (or as a home backup when the cable/DSL is out) and works well on USB and slightly less so over Bluetooth, so long as AT&T has service in the area - which isn't always.
But AT&T, while encouraging it o
