cristoff:
probably your connection that's bad. it's working fine for me and has been all week. streamed films, on demand football highlights, live sport and it's never had to buffer once on high quality. and that's through wireless.
the high quality isn't actually high though...it's low quality encoding, but it's costing me nowt but a couple of beers thanks to some generous friends so who am i to complain? nice addition to the xbox family i think.
I havent used it, i know three friends who've had it, and had many messages on XBL saying its bad.
One friend is on Virgin 50MB and its jittery, i considering he gets his 50Mbit downloads and 2Mbit(i think) uploads, it should be fine considering hes over the recommended.