Any questions you have on bandwidth and lag is answer in the press conference. 5mps (MAX) for hd tv, granted most things are running at 2-4 tops. this wont replace your ps3/xbox360 for a while since they have first party owned games like halo and killzone.

If you do not have at least any type of Duel Core CPU and at least a nvidia 8 series or ati equiv, and 2 gb of ram your going to jug along with bad fps