I'm gonna go ahead and guess you'll install Cataclysm, get a cut scene showing what happens to the world, then it'll be changed, and anyone not buying the expansion will get the cutscene in a patch, so everyone's on the same world on release date.
I sense I might actually end up being one of those weirdos who goes to a midnight release this time
I sense I might actually end up being one of those weirdos who goes to a midnight release this time