I had a late 2007 model 2.2Ghz MacBook. It was hot. Cook my future babies hot. When I would hit Youtube, the fans would come on full blast. Load up Civ IV? Fans on full blast. Sometimes just sitting in bed with it would trigger the fans due to reduced air flow. Run Bittorrent? Fans on full blast. Encode tracks to AAC? Fans on. My friend has the exact same model with the exact same behavior. I snagged the new 2.0Ghz MacBook. This this runs cool. Super cool. Super quiet. Even under the highest stress, I barely hear the fan. I can encode AAC and watch an HD video at the same time, in total silence. Now I can play Civ IV without being forced to use headphones just so I can hear the sound over the fans. This unmarketed "feature" alone is worth the money for the upgrade.