I'm certainly not sure, but I think the JVC 90 has a built-in, high-res digital still camera, with flash. They store their photos on a Panasonic SD card, which mounts in behind the LCD screen. They're pretty cool, but if you've already got a nice still camera, just get the lower model.
I've got two nice digital still cameras (both 2.0+ megapixel, so low-tech now...
), so I just got the camera with the "snapshot" function, which saves 3 seconds of still image for later retrieval from the video via your PC.
Whatever camera you buy, make sure it's got a Firewire port. It makes transfer to your PC for home editing easy and fast!