no cap yet.
They could cap non-Uverse SD/HD Tv traffic easily.
Uverse doesn't cap, but is using the same DSL infrastructure and cable plants, but using bonding VDSL technology. Bittorrent over Uverse will give the same problems it does over standard DSL, sucks up the bandwidth. Now it will be effecting the SD/HD TV streams being deployed over the AT&T network. Hopefully AT&T has QOS that will always deliver SD/TV over bittorrent.
Remember this is the same company that said the internet was running out of bandwidth.