I'll have to look into this ... The file chooser is a built-in component (though source is available and you can override most behaviors). I've never tried to modify that particular component before though. Or would it always be "jump-to-title"?
So if you hit a key in the table view (of the playlists) would you expect it to jump to the "T" of the currently sorted column? (i.e. if you sort by Title, "T" would go to "Tonemian Rhapsody", but if you sort by artist and hit "T" then it would go to "Tony Fabris"?)
Mike