I stayed with three other co-workers for Google I/O and it was great. I slept on the sofa, which was very comfortable. The area is fairly quiet but it was convenient to get to Google I/O and related events around Mountain View.
The host doesn't stay in the same apartment, but nevertheless communication was great - some problems (outside of Carol's control) cropped up and she helped us with them very quickly, and she was generally very accommodating.