For me Vimeo works pretty well. It does depend on the time of day a bit and possibly where I'm at (home, work, road) how well HD content plays.

I do let it buffer a little longer by pausing the playback for a few seconds when I'm on a slower link or there is some "internet congestion" along the way.

However when the bandwidth is enough it plays through straight away, even on my older cheapo windows notebook and even older G5 2.0 DP. And I'm a long ways away (Europe) and only have 2mbps dsl lines at home and office.

I have noticed that lately it seems to 'stutter' more often then, let's say, 3-4 months back. Maybe it's because of more people using it now.

George/