Why can't we have a robot that maps the surface and then cleans accordingly? I always get irritated when I look at my Roomba doing it's job.
Disclaimer: I worked on it.
Edit: To answer your question directly, you have 3 choices:
1. Don't map (or somewhat guess it) - Roomba.
2. Map first, then clean - Neato.
3. Map as you clean - Dyson 360 Eye.
This is obviously a crude explanation but they get harder going down the list. If you are interested to know more, read up on SLAM (Simultaneous Localisation and Mapping) algorithms.
Edit: thanks, you answered while I was asking. That's a very interesting use case for SLAM. Does it re-map every use (i.e. today there's toys on the floor, but tomorrow there's not)? Does it store the point cloud or convert it to something more manageable? Are you licensing someone's SLAM library or did you roll your own?
Sorry!
http://www.designboom.com/weblog/images/images_2/jenny/roomb...
I tried a Neato but it was much more prone to getting stuck (every single time actually). Obviously that will vary depending on your furniture.
The answer is of course "it depends." Certainly the Roomba could be smarter, faster, and more efficient, but the question is how much more are customers willing to pay for those.