Perhaps they did, but it didn't seem to cost nvidia too much, they are still in all the mac computers. And meanwhile all of us with $3000 MBPs are just waiting for the chips to explode before we get another one put in that will just do the same. Somewhat frustrating even if it isn't Apple's fault directly.
apple has been replacing units more then the cards themselves....and this fiasco has cost nvidia over 200 million so far....probably more now.
apple cannot change the design now....its done so they have to keep with the current design....in my opinion they should replace any machine showing the gpu problem with a unibody machine...but that would cost a fortune, so the buck is passed on to the customer....even though it shouldent be.