The Cupertino-based company has once again managed to hit the nail right in the head, at least when it comes to the latest Mac OS X version: 10.8 Mountain Lion.
After hundreds of users complained on the official Apple discussion thread and several tests were made, it seems that by upgrading to Mountain Lion the battery life of any portable device will be drastically reduced.
The first signs of a weaker battery on Mountain Lion appeared right from the first day, when several users have claimed to get significantly less life battery life after upgrading to the new version.
The reduction in battery life was somewhere around 50%, and this goes for any device that supports Mac OS X 10.8 at all: MacBook, MacBook Pro and MacBook Air.
The Mountain Lion battery bug is clearly related to the operating system and not to the device itself, as testing showed that during a normal usage cycle, where the CPU activity rarely peaks above 20%, the performance of the battery has dropped from 8 to 5 hours, on a MacBook Pro with Retina display.
The only cure would seem to be an Apple-issued update, which will hopefully arrive soon on the Mac App Store. Until then, let us know in the comments if the Mountain Lion battery bug has affected you.