There's a remote chance I could learn something from previews or reviews from prior to Amazon's release date that would cause me not to buy at least the core books, but that's really unlikely. Now, I'm not the regular DM for my group -- in six years of playing with them, I've run six weeks of a SWSE game -- so I can't dictate what we play, and I won't buy more than the core books unless I'm regularly playing the game. But I've got a lot of games on my bookshelf that I'm sure will get less play time than 4e will.