T-Mobile is currently the only U.S. major carry that doesn’t currently offer the iPhone, primarily because T-Mobile uses Advanced Wireless Services (AWS) spectrum band for their 3G network.
Several news sites are now reporting that AWS chipset support is on the way, and may make it into the next iPhone. As as a result, you will soon be able to purchase an iPhone and use 3G on T-Mobile.
Currently, I’m using an iPhone 4S on T-Mobile, but I only get Edge speeds, but the price is far less than AT&T.
