Hi John:
I think you misunderstand Chris's request and mine. With a media receiver, you can play files one of two ways:
1) You start the uPnP server, then turn on your TV (if the media receiver works through the TV) or the receiver's display, and using the remote control of your media receiver you navigate through the menus of your uPnP software (i.e. MediaCenter) and choose the songs/playlists/albums, etc. you want.
2) You actually use a Media Controller, like CIDERO, so that you queue up your playlist and your songs from your computer and start them to play on the media receiver. This way, you do not need to turn on your tv, or to have the remote controller for your media receiver available.
Therefore, if MediaCenter were to support the functions CIDERO did and be able to queue up music to the media receiver, you would simply use your computer to select the songs you want to play and simply send that information to the media receiver. The songs you are organizing and selecting are what is in the library of the MediaCenter, not elsewhere. So in essence it would "push" the music to the media receiver, instead of the current way of having to "pull" the music from MediaCenter using the media receiver.
Was I able to explain the concept?