I am trying to decide between the two cpu models of iMac for my wife. Se does not need the extra power, so I wanted to save the $300. The core2duo is more than fast enough for her. But- I don't want the machine to get left behind in the next OS upgrade, r even possibly 10.8. I remember there was a clear line between the core duo processors and the core2duos in terms of being able to handle 64 bit stuff. Does anyone have thoughts on whether there will be some significant level of functionality that the i5 would bring, based on Apple's likely direction with its next OS? Any thoughts would be appreciated.