As far as listening to binaural recordings while on the move, check out the Etymotic ER-4B in-ear headphones http://www.etymotic.com/ephp/er4.aspx. The 4B model is specifically designed to reproduce binaural recordings, and they all have excellent sound isolation characteristics (in case your listening environment is less than ideal) - typically 35-40 dB isolation. Price is about $250-300, and you'll certainly have to order the 4B, as stores tend to focus on the 4P.
As far as UPnP, I'm leaning toward a dedicated NAS device with all my media on it, and with the option (?) of using the N810 as a remote of some sort. This is well beyond my areas of expertise, and as I said, I only started looking at it yesterday, so I don't have much to add just yet. Maybe in a few weeks. Perhaps Canola could be used as a UPnP source/controller?