Speed is a limit, a restriction when it's arbitrarily controlled in a different way for some users. When speed is slowed, the user cannot stream video and load web pages and therefore cannot use the device in the way it is designed and promoted. AT&T boasts it is the nations fastest 3G network. They hitched their wagon to a particular feature: speed. They're not selling based on great call quality, low prices or better coverage. AT&T has two things going for it: simultaneous voice and data and very fast download speeds. I think it's a bad public relations move to try to squeeze a few dollars out of a few customers by giving them the speeds of their closest competitor. 

AT&T made it totally clear from the first day of the iPhone (when they had an exclusive) that they don't want the iPhone to be used like a laptop. That's why they wouldn't enable tethering for the iPhone. When they finally allowed it, saying they had to upgrade the network first, they only allowed it with a big plan price of $45 for 4GB. (Well, look here! We just found  more GB's for you -- at the speeds the nation's fastest network can provide.)

As I've said, I've never gone near the 2GB line. I've paid so far $75 extra for the ability to exceed that amount if circumstances require. I'd be very, very irritated and unhappy if I got into a situation where I needed to use 3 or 4GB and my service became unusable.  As it is, I can't download large files on the network.