I believe the only camera that has this capability is the Nikon D90. The problem with shooting video with this is manual focus. So if you set it up on a tripod focussed and as long as you don't move it you will get great video. If you have experience in the past you can get by shooting video via manual focus if you are fast enough. I was in a Henry's a few weeks ago and one of the salesguy there was able to do it but he's been shooting manual for 20+ years.
Best thing to do is get two seperate devices, a nice SLR camera and a nice HD video camcorder.
Thanks guys. Looks like this HD photo camera thing is another marketing trick. Just like the 14 magapixels but still keeping the small senors. Or, the camera that has an ISO of 12,000.