ATT does this because 90% of people go no where near their limit.
Find out when your month switches over - The day before, stream Netflix until you are .2gb away from your limit then stop.
Repeat every month and watch ATT take it all away.
I doubt that since Netflix pays att for priorty on their network. In all likely hood I think att will continue to add data to their existing plans because it's already out they plan on streaming dtv and uverse to all mobile devices at no extra charge.