Windows Speech Recognition Macros
A Technical Preview of Windows Speech Recognition Macros, WSRMacros, has just been released!
Like the name suggest it allows you to create Macros for Vista's Speech Recogntion. You don't need to know anything about SAPI to work create a simple application. I'm still installing and playing with it, but something you could create is a macro that would allow you to say "Play <Song>" and it would play that selection.