OK, this isn't funny!
Just hours after replying to the above I actually got my MAXX HD. Mine doesn't rotate on the home screen either. No hardware problem, any data entry screens rotate just fine as do the apps I've tried... it's just the desktop so far, for me, and related screens. In settings, auto rotate is checked. I also tried unchecking it, then rechecking it. No dice.
What gives? I USUALLY use the phone in what I call landscape mode (long axis horizontal). I see there are utilities that can be installed to do rotation things, but Google in its wisdom couldn't have made such a bonehead move as to disable home screen rotation. Seriously?
Any input from more experienced folks? I'm still finding my way around ICS, having come from a Droid X with Froyo.
Marc