We found it noisy, but not insufferable. I think it depends on what you are used to and how busy the BW is. We were there during baseball playoffs, which made ESPN particularly busy, and caused a few late night celebrations on the BW as teams won. We were on the second floor, however. It was significantly less noisy than the hotel room I stayed in near Fisherman's Wharf in SF.
If you live in a city or are there during a slow season or stay out late yourselves (we were trying to put kids to bed at 8:30 - with fireworks going off at 9:00) you probably won't notice any noise. On the other hand, if you are there when the BW is really hopping and trying to fall asleep at 10:00 pm and live someplace where the loudest noise is the frogs, you might think its noisy.