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After installing Mountain Lion on my MacBook Pro (2010 model) the difference in battery life was INCREDIBLY noticeable. But since I only use the laptop occasionally, I didn't worry about installing the 10.8.1 update until last night. Then I charged the battery overnight. This morning, with screen contrast set to about 20-25% and graphics switching turned on, I'm down to 86% of battery after just 20 minutes of use. Back under Lion, I'd still be in the mid-90% range after 20 minutes.

I am seriously considering restoring Lion from a backup. This Mountain Lion reduced battery life is real and very annoying!

Mark
 
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