Actually one of my mates has a previous gen imac with 12gb of ram installed..... And my school has a room of previous gen imacs ALL running 6gb.
EDIT: seems previous gen is not 2006 model as I thought. You are indeed correct although it seems like a false economy to buy such a machine. That limit is also software enforced not hardware enforced, the chipset apparently supports 8.

My research is still showing about a 30% cost increase on the older apple hardware compared to a new windows machine. Not as bad as when I got my laptop I guess, I paid £379 and the equivalent ibook (macbook didn't exist yet) was £1200.

Actually one of my mates has a previous gen imac with 12gb of ram installed..... And my school has a room of previous gen imacs ALL running 6gb.

My research is still showing about a 30% cost increase on the older apple hardware compared to a new windows machine. Not as bad as when I got my laptop I guess, I paid £379 and the equivalent ibook (macbook didn't exist yet) was £1200.