Ever since I upgraded my MacBook to Leopard, and specifically to 10.5.2, I'm noticing that I'm getting much better battery life on this machine versus when it ran Tiger. This is a 1.83 GHz Core Duo MacBook, 2 GB of RAM, with a WD 120 GB hard drive. Previously, with Tiger and I how I typically use the computer, I would normally get around 2 hours to 2 hours, 15 minutes of life before getting a "You are now running on reserved power" warning message. Now, I'm routinely getting close to 2.5 hours of battery life. And today, it pushed 2 hours 35 minutes. I normally use my machine at three-quarters brightness and have the setting for "better energy savings" on battery power. I do "office-type" work, and surf the web. Sometimes I have music on in the background, other times not. Has anybody else noticed this with Leopard and 10.5.2? Needless to say, I'm happy with this result.