I just bumped up my MBP i7 to 8GB RAM. I'm noticing less fan burn than usual. That is to say, the fans to cool things down don't seem to run on high hardly at all. With just 4GB they came on nearly every time flash cranked up or during a skype call. Not any more. I don't know exactly why that is. My best guess is there is less paging from memory to disk, so the system isn't working as hard. Anyone else have a more educated guess than that?