I have to admit, I wouldn't mind the ability, either. Theoretically, the only real change to the outside of the camera that would be necessary would be the addition of a microphone somewhere. Most of the time, I don't demand much from my video-taking, so just some basic functionality would be appreciated.
The K20D is already almost there with 20 fps at 1.6 megapixels, much larger than you get in the video mode of a point-n-shoot, though at fewer fps and with no sound and I believe no autofocusing. Of course, it creates a lot of files very quickly and you don't have the capability of recording until the card is full, either.
OK, granted, I would rarely use such a feature, just like I'll rarely use Live View, but I think it's somewhat snobbish to demand that new features not be included in a camera as long as they don't affect its primary functions. Surely there were complainers when "new-fangled" features like autofocus and automatic metering were added to cameras.