Love this thread. Since I don't have a dedicated music system, I've been using HomeMedia for music listening exclusively.
A better search function (even though it is dependent on the server), and Net Radio (even though it could be in a separate source) would be great.
Twonky has the "INDEX" option, which sorts the media in three letter increments (ABC, DEF, etc), but that's still not convenient enough.
As I've mentioned in a previous thread, NetRadio (software functionality) being sequestered to the Avant as a purely marketing decision seems uncharacteristic.