People still do cheer and howl at sunset (and sunrise, to a lesser degree) and they have every year that I've been there. The 1st time I heard it, it took me totally
by surprise and I couldn't figure it out until the next. "Good lord, what is everyone cheering at? What incredible mutant vehicle must be passing? Is there a parade? Why is some guy a half mile away cheering too?" Needless to say, I couldn't have been on the Esplanade at the time, or it would have been more obvious.
After you get used to the sunset cheers, the first time you're awake for sunrise and it happens again (even though it seems less likely) it's kinda wonderful.
I've mentioned it before once or twice to virgins, but I've stopped doing that spontaneously. I don't want to take the surprise away from anyone.
Also . . . the scattered nature of many small cheering sections, sometimes miles apart, makes for an eerily beautiful sound. I'm sure if the whole city was doing it, it'd be interesting to hear how it changes, but I kind of like the strange quality of the sound right now.