Tore, yes you're right that sonos is audio-only... but check out
www.xlobby.com . It's NET, outputs 3 or more music sources from a single soundblaster (each speaker pair is a separate source) plus video via TV, TV recording, yada yada yada ... Media Center can do a lot of it but not (yet) the source splitting via soundblaster.
FWIW, we've found that a chipped original Xbox is a fantastic media server/media appliance- far more so than the Xbox 360. Check out
http://sourceforge.net/projects/xbmc/ .
"... They ne'er cared for us
yet: suffer us to famish, and their store-houses
crammed with grain; make edicts for usury, to
support usurers; repeal daily any wholesome act
established against the rich, and provide more
piercing statutes daily, to chain up and restrain
the poor. If the wars eat us not up, they will; and
there's all the love they bear us."
-- Shakespeare: Coriolanus, Act 1, scene 1
