Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Amazon always offers Apple products slightly below Apple's retail. The current offers have been in place for quite some time.

With that said, we also know that the iMac is due for an update any time now, so my strategy is to wait another up to a few more months for that update. Then if its not that significant of an update, I'll grab a current generation machine at a deeper discount or if it is a good update I'll grab a new one.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.