"The saturation point came when it opted to serve as title sponsor for the AT&T National, the event hosted by Tiger Woods."

Stan Awtrey details AT&T's decision to opt of the Atlanta tour stop after 2008 and includes this:

The saturation point came when it opted to serve as title sponsor for the AT&T National, the event hosted by Tiger Woods.
And when the decision was made to dump a tournament, the Atlanta tournament — not the one affiliated with Woods — drew the short straw. AT&T officials notified Kaplan that it was invoking an escape clause, which allowed the corporation to withdraw upon giving a six-month notification.

It's amazing what havoc the Tour's decision to abandon the Chicago/Western July 4 date has wreaked: the demise of the International, horrible press and fan relations in Chicago that the Tour is trying to remedy, and now one less sponsor for Atlanta. I'm sure there's something else I'm forgetting.