MacBook Air vs. Ultrabook(s) Battery Longevity
You can now expect to get a whopping 15 hours of battery life on Mac OS X 10.9 Mavericks when using the 13" MacBook Air. A huge improvement over Mountain Lion, which only had a mere 12 hours of battery life on the MacBook Air. And of course both, easily trump the batteries found in Windows Ultrabooks, where you can expect around 10 hours of usage on their premium ultrabooks. Hopefully the Windows side will be able to catch up in the near future.