First, I have to say I absolutely love my new 15" Macbook Pro. I came from a Powerbook G4, which I was still getting by with, so obviously it's a huge improvement. Originally purchased the 2.3 ghz w/ ssd version, but then the spec update happened. Was still within the window of a return, so decided might as well do a switch as the price was the same. Didn't realize the return process (via online) was so easy and straightforward. So kudos to Apple for that. Received the new computer, 2.5 ghz w/ ssd, the other day and am happy that I made the switch as it wasn't much trouble at all. However, one thing I noticed is that the computer is a bit louder then the previous 2.3 ghz one I had. Still very silent, but I definitely hear the fan more often. Kind of bummed by that a bit, as with the old one, only noticed the fan on rare occasions and loved how absolutely quiet it was. Is it correct to assume that the 2.5ghz chip just runs hotter, so the fan RPMs are higher more often? It's also 1 oz heavier then the other one. I doubt I would have ever noticed the performance upgrade, so almost makes me wish I would have just kept the old one.