I pre-ordered this and got it soon after the release and can't think of a reason to never use it. This is not just a photo tracker, but a full-fledged GPS tracker with excellent battery life. Think of the fun, hide it in a car of someone you don't quite trust and then retrieve it later. The software uses Google Maps to route tracker, and it matches the time code on digital pictures to the time code on the GPS files. If you go inside a building, the signal will be lost, but the software is smart enough to assume you're in the same place. The pictures upload to Flickr with a couple clicks and so long as you hard encode the GPS data to the picture files, Flickr will map them for the world to see.
This works with any camera, because all you have to do is match the time.
Also included in the box is a travel adapter, which is a USB charger that plugs into a car outlet, a home charger, and the needed cables. This works perfect in pockets, bags, and picks up a signal faster than my Garmin car unit.
This is the best device until a camera is released with a built-in GPS tracker.