For me there is now only one reason I am with AT&T. It's the iPhone. I pay outrageous prices compared to my friends who are with other networks and on similar packages. Customer care is zero to none and recently dropped calls have caused me some pretty major embarrassment with my clients. The fact that AT&T was not ready when MMS messaging was made available on the iphone along with tethering just adds to my AT&T frustrations. AT&T really could have owned the cellular market with some wise decisions to go along with the one right decision they made in carrying the iPhone. Short sightedness and some really bad management kept that from happening. I predict a huge migration to the first carrier outside of AT&T offering the iPhone.
Weird that a fine company like apple has chosen one of the worst companies in AT&T to manage its iPhone sales in the US.
Stuff like the MMS and tethering delay is just crazy, and seems unique amongst the world. Over here there is something like 4 or 5 phone companies that have stacks of the iPhone for everyone. Only one of those companies sought a slight delay with tethering - the rest offerred MMS and tethering ready to go on the day Apple rolled out the capability.