Well, results for me seem to be very positive. The popping sound I experienced actually never happened while I was using the device, aside from the trick used to trigger it. It would always happen when the device was sitting idle, locked, and a notification came through. It didn't matter how loud or quiet I had the notification volume set, right before the notification tone played, a terribly loud pop would emanate from the speakers. This behavior was very erratic...sometimes I'd get 5 e-mails in 15 minutes, and it would happen every single time. Sometimes it would go a few hours before happening, and then not happen again for another few.
So, it's still early to say for sure, but since the update I've had an exorbitant amount of notifications come through, and not once has it popped, not a single time. I cannot trigger the pop using the known swiping method either. I've been sitting with it all day, and nothing....tried swiping up and down about a hundred times, and nothing. No pops. Keyboard clicks and lock sounds are turned on, btw
If anything changes, I'll be sure to chime in with my disappointment. But I've just not been able to reproduce the speaker pop at all today.