I'll probably buy Pioneer next time. My Panasonic plasma started the shutdown problem only after 3 years. I've found out at avsforum.com that this is a common problem that Panasonic won't address.
http://www.avsforum.com/avs-vb/showthread.php?t=302017
http://www.avsforum.com/avs-vb/showthread.php?t=302017