Hard Disk camcorders are equipped with a safety feature that when a sudden displacement occurs, the camcorder locks the hard drive (takes the heads off the platters) so no scratches or damage is done to the platters themselves. I've seen some who have dropped it from 5 feet and it still works perfectly.

If you drop it above 5 feet, chances are that the camcorder itself will not survive. Most damage would be done to the body, sensor, or mechanisms. And that goes for ALL camcorders, including MiniDV, DVD, and HDD. Always remember to use a good quality case with padding for any camcorder.