Thanks for all the information, I am trying to get my A / V receiver remote to control the Rio, and as it is not a learning remote, I was hoping the Rio just might match some popular CD-Player's control signals. If anyone has found a compatible unit that the Rio understands please let me know.
What I really would like to see, is a firmware update that allows Streaming MP3's to be player from the server, such as Internet Radio or even my own local LAN based MP3 Radio station. Then I could use a wireless laptop to control the song selection. Plus, finally read the song currently playing.
I am looking into the Rio Hack http://www.mock.com/receiver/server/
At least using this you can incrementally add songs to the database, while the receiver is still playing. Hope some of this makes it into a future update.