I just recently myself picked up one of www.helmetcamera.com's 560 line helmet cams with the DVR.
Comments on the DVR:
record quality is as they say: NOT "broadcast". It's good for sharing with friends, showing on a TV with some apparent loss of resolution, great for web-based stuff.
Pros: TINY! The DVR is the size of my Blackberry Pearl: 9cm x 5.5cm x 1.1 cm thick. It's size and bulk means I can pack it anywhere to keep it from the elements. Unless you're diving I wouldn't go with their waterproof pelican case system.
The whole camera set up seems pretty bombproof
Camera can be hardwired to bike (12V)
records to SD and is easily read by PC or Mac
Cons: DVR doesn't seem very tough, and there's no name brand on it. But again, for it's size it's easy to protect, and if something does bugger, it's only a few hundred $ to replace.
no remote record button. I'm going to try keeping mine in my tankbag mapcover, see how that works.
DVR can't be readily hardwired, although will charge off of USB.
Here's a pic of everything I need to capture video. Camera plugs into 12v DC hardwired on an f650 GS:
EDIT: I don't need the Leatherman or the BB to film. They're just for scale.