New iMac's have 4 memory slots, meaning that the buyer can get 8gigs of RAM by purchasing 4 2gig memory sticks at a much reduced price ($200 or less) than having to buy 2 4gig memory slots (at $500+). It would have made more sense if they released the Early 2009 iMac's with DDR2 RAM instead since it would have been a more affordable alternative. 