The Neato XV-11 arrived; after a full charge, it ran around the un-cleaned-up first floor of my house with very little trouble - it had a little trouble climbing some sills between tile and wood floors (which the Roomba just bounced off of, the XV-11 seemed have a more directed set of attacks that eventually worked.) It also found most of the places it could go before coming back for a charge (with a 3/4 full dustbin, though it left some small scraps of paper - not too surprising for suction on hardwood. It also wasn't very effective on birdseed on a doormat, though I'm not sure anything else will be either.)
There were a few areas it seemed to just avoid - I wonder if there are magnetic bits underneath them (nails in beams, perhaps) and it would be nice to have a diagnostic from the unit that actually reported such, maybe by blinking the backlight on the display or something.
It is a bit loud (more broad-spectrum than piercing, though) but the whole point is to let it operate unattended, and after this first pass, I'm much more willing to leave it alone in the clutter than I would be with the Roomba. It's also interesting to see it explicitly shut the "vacuum" off and display "returning to charger" as it quietly heads "home"; it helps make the case that it knows "where it is".
It'll need more observation... and eventually, video of the XV-11 and one of the Roomba's attacking the same floor :-) But for now I'm happy with watching it attempt "real" work that isn't set up to challenge it...