minus the courts have already said otherwise.
Unlimited does not mean excessive usage. That little part gives them a lot of room to play around in at were they started declaring excessive usage. Chances are all they need to do is prove you are in the top 1-2% of people data wise and they can nail you for it. Just show that the person is an outlier and you can be hit.
I personally would rather say AT&T just start throttling the people busting 5gigs and limit them to edge speeds or slower. I am tired of being on the side that has my service screwed up by the data hogs. Limit their speed.
Honestly AT&T could care less if those 3% or so of people left and went to another carrier. They are negative profit to AT&T any how. To AT&T they figure some one else can loss money on having them.
5gigs is about the break even point for $30 a month data plan for AT&T.