Don't know if I'm expert enough to reply but I went ahead and bought this player a couple of months ago, so for what it's worth:
This is my third player the others being a Samsung and a Panasonic. Picture quality from the Denon seems much better than the others in terms of clarity and colour. However, it is on the audio side that things very much improve. For b/ray I use the pure direct mode on my amp and the steering, to my ears, is excellent. The quality of playback on cd's is vastly improved as with DVD audio. I only have two SCAD discs but the result of playing them on the Denon is impressive particularly when I compare them to their cd version.
Works well with my media server (wired not wireless)
Loading times are possibly not the quickest but not particularly slow either. Really the only negative comment I can make is that there is a fair amount of mechanical noise when loading a b/ray but this goes away when you start the film.
Afraid I am unable to comment on the 3D function as I'm not even sure the up-date needed for it has been released. It did connect to the internet the first time I switched it on and downloaded an up-date but even after going to the Denon site I can't tell if this was for the 3D function (anyone know if this function is released yet? it was due at the end of Jan). I'm still saving the pennies for a 3D TV and for the new models to arrive in the shops.
Hope this helps!