The list will be a mile long.
Russound has 5 options (Sphere, Collage, CAM, CAV, Essentia), Nuvo at least 3.
Depends on how much you want to spend. Don't forget the cost of the source components in the overall price.
I have been shopping for a new distributed audio system for months, myself.
The visible, distributed metadata is the tricky part, IMO. Nuvo GC and Russound CAM/CAV are leading my least.
Don't forget the Speakercraft MODE system. The Niles ICS is pretty slick as well.
Please post your progress.
Edit - of course you wouldn't consider the Collage. I'm most impressed by the Sphere, though the hardware and software are fairly protected - maybe you could buy from an authorized local dealer, and pay him a little extra, you know, 'for the effort'.
Read about Nuvo Music Port for access to networked digital content.