Well, the UK situation involves three GSM carriers. In the United States, the only prominent GSM competitor to AT&T is T-Mobile, and they have no need or intention to get their phone on a budget carrier. With Verizon, they'd have to design different hardware and deal with the fact that EV-DO Rev. A on CDMA is on the way out and LTE is going to be lit up for about 100M subscribers by January 2011.

So in other words, everyone in the world will be using the iPhone with their favorite carrier, and thus competes equally with Android, except for people in the States who will be stuck with AT&T for a few more years.

Bad for Apple how? AT&T is paying quite a bit for this privilege. As high as $18 / mo / iPhone according to http://news.cnet.com/8301-13579_3-9803657-37.html

Right now I think Apple cares more about the image AT&T is giving the iPhone than the money their paying for the privilege. The iPhone is not just for 5 Christmas's...

With both AT&T and Verizon rolling out LTE networks over the next year, it makes little sense creating a CDMA version of the iPhone only to have an LTE iPhone replace both GSM and CDMA iPhones. I think its more likely that the next iPhone could be on Verizon first, then AT&T since Verizon is rolling out their LTE network faster than AT&T.

Apple has benefited far more than AT&T... look at the stock prices or revenues gained. I'm not saying they're benefitting specifically from exclusivity... they would make more with more carriers to be sure... but the notion that it's "bad for Apple" doesn't seem to float.