My zwei pfennig:
o THX ratings are pretty much meaningless these days. About all they really tell you is that the manufacturer gives the THX people a bunch of money to use their logo, which gets passed along to the consumer
o The Denon 3808 is a highly-regarded unit and if I go with M80's I'll probably spring for one myself. For M60's, though, especially given your pricepoint, you might consider the new Yamaha RX-V663 which can be had for $400-500. Compared to the Denon 3808 you don't get the network foo (which seems useless since it apparently only works with MS-DOS), downloadable firmware, and you have <wpc and one less HDMI in.
