San Jose, CA
reply to UverseTech
Prior to 2011, AT&T played with per tier caps. Something like 40 GB for Basic, 60 GB for Express, 80 GB for Pro, 100 GB for Elite, and 150 GB for U-verse. Only implemented in a couple of test markets, then withdrawn; probably due to user resistance.
Around February, 2011, they announced the return of caps; this time a simpler 150 GB for legacy ADSL, and 250 GB for U-verse. I suspect the difference is intended as an incentive in favor of moving customers from ADSL to U-verse HSI where available.
For me it was more of a dis-incentive; I kicked AT&T to the curb in favor of Sonic.net "Fusion" service.
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum