I want a REALLY smart playlist in iTunes and I can't figure out why I haven't got it yet, since I would end up spending a lot more money on the service if I had it. Right now, Apple offers what it calls Smart Playlists, which are simple scripts that select songs programmatically based on their metadata (name of artist, genre, publishing date, etc.). So a typical Smart Playlist might be "blues from the 1940s". I want a much smarter playlist: I want a celebrity playlist from Eric Clapton that will review what I have in my iTunes library already (regardless of source, whether I bought it on iTunes or ripped it from a CD or even acquired it otherwise) and then recommend how to get what I don't have in that playlist from the iTunes Music Store and tell me how much it will cost to buy those songs. I can even imagine that this really smart playlist will recommend replacing one version of a song I have with another, say that's longer or live instead of studio or that has different artists playing it.
Maybe I missed that this kind of playlist is already available?