Hmm...I think such as thing has already been done in simple form. I'm not sure if DB/Pro supports enough sound features to port Winamp to it, and you'd probably have to have the BlueGUI plugin for it to be usable. I usually do other things when I listen to music, so I don't like having a fullscreen window telling me "Current Song Playing: blah.mp3" and the rest of the screen black, heheh. If you could make it look cool (customizable skins?), not hog too much memory (Winamp itself has this problem and I hate it...30 MB of RAM for an MP3 player?), and not slow the computer down to all hell (DB/Pro programs like to hog as much processer time as they can), it might be worth using. You'd have to give it something that makes it better than Winamp, though, heheh.
Now a DLL that could interface with Winamp, that would be interesting.