All of you are having fun complaining about AT&T, but you really should just be complaining about cell technology in general.
If you actually understand how cell phones work you would be a little more sympathetic to AT&T's position. Unfortunately there are only so many frequencies in the radio bandwidth. There is a limit as to how many devices can be functioning in any given area without interfering with each other. The concern here is that someone streaming data constantly is using an entire frequency spectrum and it can never be shared.
The entire cell phone concept was developed on a shared frequency model. With more and more people requesting data more frequently the whole model falls apart. Sure they can make cell sites smaller and smaller so as to cover less of an area (and therefore less people), but that has limits too. You can end up with weak signals and more dead spots. In high population areas this is a big problem. As time goes on and more and more people are constantly trying to receive/transmit simultaneously we will eventually run into limits.
Sure there are new technologies coming all the time to help, but they can't be implemented fast enough.
AT&T is quickly realizing this new direction the wireless industry is taking. They are struggling to keep up. No cell phone network has had as much data demand as theirs, ever, thanks to the iPhone. They can't just 'add' more capacity like some of you want them to. There are FCC limits, only a narrow frequency range they can use, cell site boundaries have to be redefined to limit interference.
This is all highly simplified, but it's the basics.
If the iPhone comes to Verizon and there is a mass exodus from at&t to them, trust me, you will have the same exact issues. Verizon's current supposed superiority will no longer exist.