I've noticed that when my OMD goes into "sleep" mode, on rare occasions it does not wake up. I pull the battery to rectify the problem. I've been playing with different configurations it seems mostly related when I have Live View turned off and the EVF doesn't turn on. Anyone notice this on theirs. In running tests it seems to occur when the camera is hanging around my neck, that is I cannot recreate this issue with the camera sitting on my desk. I wonder if it could also be connected to my lens, it only has occurred when the 20mm lens is attached and not the kit lens. I think its a firmware bug only because of the intermittent nature and how it does not affect any other function of camera.