Yep, I can confirm it too and my thinking is h-d is to blame too.

Scenario from yesterday: browsing web with opera11 in portrait, all of the sudden N900 stopped reacting to any inputs. Only menu/task manager button in upper left corner was working. Used power button, its menu appeared blurred and out of focus, like some invisible dialogue/window with higher priority was opened above it.
Locked and unlocked device using hardware switch and all was fine again.