not sure if you've seen this or not yet:
http://vincentlaforet.com/
the video looks amazing to me. being able to shoot at such high iso (i heard 3200 at f/2 and 1/15s) makes the video look a bit like HDR which is pretty cool. I was never into video before but this makes me want to get pretty creative with it.
also, the nikon d90 (i think...) shoots video but it has this crazy problem where if you move the camera horizontally while you're shooting something vertical like a pole or a pillar (or person i guess) the sensor lags and your pole/pillar/etc. sway like a belly dancer... i cant find the video but it looked pretty bad.
personally, i normally never use iso past 100 for portraiture and i do, i sometimes like the look of the grain. i only really need one focus point so i dont even need the 1ds AF. i only care about image quality and the original 5d made incredible photos. the mkII looks even better and the video is a really cool added bonus which is why im saving up for it. ding!