Mac OS X 10.8.1 Improves, but Doesn't Solve, Battery Life Woes
In depth benchmarks from The Mac Observer show what can be expected with a heavy workload, and the result is that while OS X 10.8.1 offers better battery life than 10.8, it still trails 10.7.4 by 78 minutes.
"The battery life hit caused by 10.8 Mountain Lion is significant," TMO wrote. "Our 2011 MacBook Pro lost 2 hours and 10 minutes, or 33 percent, of battery operating time following the upgrade. Remove the Wi-Fi icon from the menu bar had no positive impact (in fact ,we actually lost 5 minutes of battery life)."
Similar tests from other sites reveal the same thing -- Mountain Lion is a bear on battery life, at least for now. Apple is said to be testing a new iteration, OS X 10.8.2, though it's unclear if battery life remains a focal point.