We've got 2 dogs and 2 cats - one of the reasons I love robot vacuums so much, its like the only way to stay on top of all the hair they shed daily.
The Neato and Roombas have fairly sensitive bummers on them so I don't think they would be able to hurt even the smallest of dogs or cats. Even with limited vision I think her dog would hear it coming. Pets are typically pretty attentive to these things until they get used to it - now mine just ignore it (except to get out of the way).
I think the Neato would make a better gift for parents than a Roomba BTW, specifically because it seems to require much less maintenance. On my Roomba I need to clean the brushes after every run and use a modded cleaning head module to keep the hair out of the gears. The stock Neato doesn't have problem with hair the same way and I only clean the brush once a week or so. It also just plain "sucks" more - and cleans better as a result, the Roomba really only worked as a really good broom - it is all about the brushes but the Neato is a legitimate vacuum too.