Now that OS X 10.8.1 is here, has battery life really improved, as rumored? The Mac Observer did some tests, and the answer is… sometimes?

When Apple released OS X 10.8 (Mountain Lion) back in July, one of the few things users complained about was its impact on MacBook battery life. The software seemingly contains a frustrating bug that causes some of Apple’s notebooks to lose around 38% of their normal charge.

Apple has been working on a fix that will be distributed with the OS X 10.8.1 update. And according to one registered developer who’s currently testing the beta, it significantly improves battery life by adding up to four hours.