I think hi-rez two-channel is the way to go. Multichannel!? Come on, this seems like nothing more than a souped-up modern version of the embarassingly awful quadrophonic scheme from the 70's.
I think that multi-channel audio will be used by the "early adopters" with deep pockets, but I do not believe that the general public will go for it. Thus, I'd be surprised if in five years multichannel is little more than a faded memory.
If john q. consumer doesn't buy it, recording labels won't create the software.
I'm sure there will always be a few titles available from specialty audiophile labels, but I wouldn't want to sink big bucks into a system that will ultimately support such a limited number of recordings.