There's been a few reports of 7D's freezing after installing the new firmware. OP is your 7D totally dead or does it turn on and then start having problems. If it turns on to start with, try turning off the Auto Power Off option in the menu as others have said this stops the freezing. Canon should be releasing the fix to the firmware around the middle of this month, but if it still has the problem I'd suggest returning it to Canon for them to have a look. Most users haven't had a problem which would make this even more irritating. I don't have a 7D at the moment but might be inclined to get one once the problem has been sorted. The one I did have had occasional problems with exposure and focus so I passed it on a nd got a 5D3 and 60D instead.
