Apple just introduced a new OS X feature here at WWDC 2012 called Power Nap. It lets your Mac update email, notifications and even photos in the background. According to the company, the feature will work with the new MacBook Pros announced today, as well as the second-generation Air, which makes us wonder if older Macs are otherwise excluded. Developing Myriam Joire contributed to this report.Apple introduces Power Nap, updates your Mac while it's
