Very noisy, but we enjoyed POP so much in general that the noise would not stop us from staying there again. Next time we will bring a white noise machine (seemed to help during our recent stay at AllStar Movies) and will request a room at the end of a corridor (we were near the elevators and stairs, just a few rooms down).
Most of the noise was not from neighbors talking, flushing the toilet, etc. but from kids running up and down the corridors and yelling. Even though we were on the top floor, the way the sound reverberates at POP made it seem like kids were running on the floor above (of course there was no floor above!)
As others have mentioned, we are used to living in a very quiet place (house on an acre, and we have no children) so noise probably bothers us more than it would someone who lives in an apartment. However, we did not find AllStar Movies to be very noisy at all, and the Dolphin is absolutely silent--have never heard a thing there! We were also just at a Days Inn near DTD Friday night, and that was also very quiet.