My friend Matt just got a Canon 5D mkII and shot us this video from his balcony in the Eurolands. The file was about 450MB for around 90 seconds of shooting. It's a very, very dark shot, but that's sort of the point; it was almost pitch dark outside on his balcony and he still was picking up a lot of light. (I think it's kind of pretty, actually, especially when the train rolls by.)
Here's Matt's tech description:
This is a test shot from my balcony with a 5d mkII. it's pitch dark outside - correct exposure for the bright areas of the frame is something around a second, f:1.8 for iso 400. the lens is the 28 1.8, i'd assume it's shooting wide open and at 3200 iso. the camera is handheld. the card is a sandisk extreme iii, which seemed to work just fine. i tried with an old ultra, and it buffered out after about 5 seconds.
Can't wait to see what it looks like with some daytime light — and what Matt, one amazing photographer, does with it as a plain ol' DSLR.