Seems shortsighted for everyone, honestly.
Shortsighted for Amazon since they're going to lose some amount of pre-orders and orders, not to mention the extras that people add on to get free shipping. And then Warner is losing one of the largest retailers for their product. Sure, it will be available on the site in the long run, but not when it may be top of mind for some consumers (ie. when it's announced).
Should I even mention how terrible Best Buy is this week? I planned on walking over at lunch on Friday to grab Superman, Batman and The Birdcage. The store I would walk do doesn't have stock of any of them. So chances are I'll be driving to a store (*sigh*) this weekend instead of getting a 2 mile-ish walk.
Yeah, I know...I'm just complaining to complain now...