No the world change applies to everyone. And Cata's $40. I would advise just getting classic WoW and buying the xpacs as you get close to the level caps (when you get close to 60ish buy TBC, 70ish buy WotLK, etc). That way if you don't like it, or take a break or w/e, then you don't spend money on it.
Find any Diablo news? Contact me or anyone else on the news team.
DiabloFans: Facebook, Twitter, YouTube, Live Chat