iRobot has had so much success with its Roomba robotic floor vacuum that it now has six different variations of the little guy. Units run from $150 to $350. The high-end versions have more convenience features, such as the ability to find their own charging station and dock, but basically all of the Roombas have the same core hardware that vacuums floors.
iRobot's new Scooba, on the other hand, does something new: it washes hard floors. In one pass, it sweeps up loose dirt, squirts a cleaning solution down onto the floor, scrubs, and suctions up the dirty water.
There's no automatic charging station for the Scooba, since the designers don't want a machine full of dirty water going unattended for too long. The machine is also more expensive than the Roomba: it's $400.
There is no news on the window-cleaning version yet.