My friend has a Linux PC and when he inserts a CD or DVD, it popups up the cover art automatically and displays all sorts of extended data, like the actors in the film, the studio that released the cd, etc. And we tried 100 or so discs and it recognized every one perfectly, just as good as Windows XP Media Center does, and it even seems to cache the entries since the 2nd time you insert the disc the recognition is instant (first time takes a few seconds). None of the other Linux media players I've used do this--they all use freedb which doesn't work for DVD's, doesn't have extended attributes, and doesn't display any cover art.
I've been poking around all day to figure out how it's done. Someone said it seems this Linux project is pulling the data from Microsoft's Windows media server, like XP MC. If that's true, I'm sure Bill isn't too happy. But anyway I figured that code must have been lifted from Wine--part of your "emulation".
But I've been digging into Wine and it seems Wine doesn't do this either, at least not anymore. In fact it's conspicuously missing since Wine is a Windows emulator, and under Windows you put a movie in the drive and see the cover art and all the info on the disc, and with Wine you don't. Was this in Wine at some point, and then got yanked because of threats from Microsoft? I actually see no reference to it anywhere. If it's another one of those modules like libdvdcss that every needs to have, but nobody wants to host, it's buried so far underground I can't find it. If Plutohome.org is going to have to pull it soon, somebody should mirror that stuff soon so it doesn't get lost.