We stayed at Bellagio for the first time last Christmas. My first feeling is that they're overcrowded with guests and patrons in the lobby and surrounding areas. It took us a long time to check-in. Our rooms were split-out to two different complexes even though we had asked to be near each other.
The room is not as clean compared with other hotels nearby. The walk way to the elevator doesn't have a security check point either so it's not that safe.