Roomba Vacuum

Roomba is interesting because it's one of the first domestic house robots that approaches Jetson-style technology. It's AI in practice.

My observations of a Roomba 440 robotic vacuum:

Doesn't seem to actually "map" the room, but rather use semi-random movement and multiple passes to be fairly thorough. Will miss some spots (but so do I when manual).
It should have an English readout in addition to beeps. Some of the beeps are ambiguous and the manual doesn't cover them.
Gets stuck temporarily on up-ward "ramp" shapes. Doesn't seem to have a movement and/or tilt sensor beyond wheel movement.
Has a "stair" detector, but still gets confused by them sometimes, requiring intervention (makes "oh oh" sound). But yet to actually fall.
Not sure it's for a bigger family because it takes a while to complete its job. Somebody will likely need the target room in that time-frame for bigger families.
It's a bit disconcerting how it bumps into things with an unpleasant thump. (Manual claims it has a scratch-free bumper.) I wonder if they could use laser triangulation to slow it down near obstacles. The bumping sometimes knocks over lightly-loaded garbage pails. Reading the web, some add felt strips to the edge.