Wait a minute... I just discovered that BIAB 2007 goes beyond just figuring out the chords to an MP3/WAV/WMA audio file - it also has a feature called "Audio Piano Roll" which displays "many of the notes found in the audio file" (quote from BIAB Upgrade User Guide pg. 6). Crazy. It looks similar to the piano roll editing you can do on SMF's with a sequencer. I'm sure the audio file it's analyzing has to be somewhat simplistic for this to work but the Audio Piano Roll is a feature I've never seen anywhere else.