two recent cameras, the Nikon D90 and Canon 5D mk II have added high def video capabilities to DSLRs. The D90, a successor to the D80 but now with the image processor of the D300 and up, does 720p at 24 fps, while the full-frame 5D mk II adds 1080p at 30 fps. Here is a piece of video shot with the D90 I found online
Nikon also has lots of video on their D90 website.
On the Canon side, the 5DmkII has far higher resolution and better low-light performance than the D90 for almost 3x the price.
Vincent Laforet (from the obscene amount of gear) has shot a very interesting video showing off the capabilities of the 5D. See it here. The video very effectively shows off the capabilities of the camera. Beautiful stuff. Also superbly deep colors. There is not much story but that is not the point I guess.
These developments are very interesting as they allow very high quality but budget movie shooting with real lenses. Game changers indeed. I don;t think I would buy either of these cameras because of this feature though. On the other hand, I think the 5D mk II is very interesting as a camera for landscapes, but financially this is not a simple thing as I would need a whole new set of lenses too.