For those of you who dislike the green button's behavior, I'd highly recommend the tiny app Right Zoom: http://m.lifehacker.com/5240827/rightzoom-makes-the-os-x-max.... It makes the green button maximize windows to the full screen size. More importantly for me, it gives a keyboard shortcut (CMD-ALT-E) for maximising a window. It's one of the few modifications I'd hate to be without.