I've noticed significantly improved performance on att's network since the arrival of iphone 4, and I now know for sure they are improving their infrastructure. In a small town that I often work in, there used to be only very unreliable edge service on att. Today I noticed nearly full bar 3g coverage throughout the town. I have to say I am pretty impressed. There are still places I travel to where att can't compete with verizon but I do think they are improving. anyone else notice similar findings?