The design is very much intentional. A huge barrier to adoption for self driving cars is perception of safety; Google wanted a car that looks safe not dangerous.
It looks like a kindergarten toy. Perhaps they should have made it look like an Escalade if they were going for the perception of safety?
Perception of safety... to other drivers on the road. This is a research prototype, there is no target consumer yet. The main goal is having a car that people will feel comfortable seeing driving itself on the street, not buying, yet. So, "toy car" is what they should be going for, at this point ;)
I guess I'll go with the default assumption that people at Google are smart. What worries me is that a company as smart and as experienced as DEKA could produce something as geeky as the Segway. Don't want to see Google afflicted by the same nerd-blindness.
an escalade is pretty shit as far as safety goes. it's an active danger to other road users and a magnet for rollovers.