I don't want to hijack someone else's thread...though i've noticed a few of them...
My camera first failed on saturday night during a shoot and i could not get it working again. The battery was nearly fully charged but i removed it anyway and replaced it with another fully charged battery. when i turned it on, i could hear the sensor shake and the top LCD screen showed the full battery indicator but nothing else came on and no buttons on the camera would work. I switched it off and went home. the next morning i opened my camera bag and it was warm inside the bag, presumably from the camera running all night even though the switch was off.
no grip, genuine pentax batteries, no unusual temperatures, never been dropped, etc. 13K shutter count, firmware 1.03 (1.11 offers no performance improvements, so i didnt upgrade)
Today i took out the camera for the first time since the incident and it fired up with no trouble. I set up my tripod to shoot something at my desk and when i pressed the shutter, nothing happened, all displays were dead. I could hear the humming of the sensor. I removed the battery and when i replaced it, the shutter fired. great, i set up the shot again using live view and when i pressed the shutter, same thing, it locked. I must assume this is the same locking up that others are experiencing?
I noticed when i switched it off while locked up, the camera remains on, as i can hear the sensor humming; this explains why my bag was warm the next day and the fresh battery was totally drained.
I am sending this back obviously...well at least i can get the electronic level fixed while i'm at it.