Microsoft recently pushed out a software update for its new Surface Pro 2 Windows 8.1 powered tablet, and if you follow AnandTech's internal testing methodology, the software patch does wonders with respect to battery life. Despite having a more power-efficient 22nm processor, the Surface Pro 2 wasn't exhibiting the best of efficiency when it came to video playback and web browsing on battery. Well, this new patch by Microsoft fixes most of the things, and while it does not make the battery life amazing, it certainly is far more attractive than it was before the update.
The results spell a 16% improvement in battery life during Video Playback on the new Surface Pro 2. Perhaps a future update will unlock more juice out of the device. For a significant change to those numbers, you will have to wait for Broadwell (based on 14nm Tri-gate manufacturing process).