It is a bit of a stretch to call this gadget a "robot," but since it comes from the iRobot folks, who pioneered the robot vacuum cleaner, it is hardly surprising. I don't think this gutter cleaning "robot" has much more intelligence than a remote control toy, but it is still a pretty good idea.
Anyone who has cleaned gutters knows what an unpleasant and potentially dangerous chore it is. With this device, you set your ladder against one end of the gutter, drop in the Looj (tm), and off it goes, crawling its way down your gutter and using a rotating paddle to eject all the leaves and trash out of the gutter. Once it reaches the end, you signal it to come back, and it backs up so you can remove it and go to the next section of gutter.
It would be most useful with homes that have long stretches of uninterrupted gutter. If you have a house with a lot of gables (and by extension, lots of short lengths of gutter), this won't be nearly as useful.