Just as a general "by the way.."
As it turns out, a little examining of Sony's announcement press release reveals the $499 model will lack support for Memory Sticks, SD and Compact Flash cards, no built-in Wi-Fi and will surprisingly have the HDMI output removed (necessary for achieving the much bragged about 1080p screen resolution).
Information found
here.
Seems like you should definitely go for the more expensive version..
JCD