+1 on the Denon 3808, mainly for these reasons:
1) better than average GUI that works over all video formats
2) network streaming of audio from networked PCs
3) network connectivity for in-home firmware updates
4) most problem-free HDMI implementation I'd seen in a receiver at the time of purchase (8 months ago)
5) everyone here recommended it to me too.
1) manual is very confusing and not terribly helpful
2) remote control is also not great - a good universal remote would help considerably
Other thoughts... it's been reported here time and again that even most receivers that say they aren't 4-ohm stable end up being just fine with the M80s. Choose your receiver based on the features you like... if there are others you're considering, definitely let this group know and there is probably a first-hand answer as to how well that receiver works with the M80s.