The idea of the cleaner is that it reduces the overall level of dirt in your house. Its a "maintenance" cleaner as it can just continuously clean. Therefore the buildup of dirt in the corners will be less as there is less dirt around generally. However you will still need a secondary vacuum to do the corners, cobwebs, stairs etc.
Its aimed at people with plenty of cash, who might not blink at having one per floor of their house.
I don't know about the 360 eye, but the roomba has a little protruding spinner (http://bit.ly/1AdpUzs) that allows it to move things into the sweeping area. Works reasonably well on corners - it doesn't get dust right in the very tight part of the corner, but neither would a regular rolling vacuum cleaner.
