Matthew wrote a great post a couple days ago about how he'll be making the jump to American Airlines for the rest of the year.
His primary reason for switching includes the following:
Frustration with United's IT System Integration More (8 on AA v. 2 on UA) Systemwide Upgrades with the Ability to be Used on Any Fare (United requires at least a W fare) Better Likelihood of Clearing with Domestic Upgrades Being Overall Slighty Disgrgruntled ...