Apple announced a new addition to the Mountain Lion/OS X family, in the name of keeping your new MacBook Pro up-to-date with relevant information concerning data stored to iCloud (email, calendar updates) via other devices, as well as keeping it current with application and various hardware updates. The new program is called "Power Nap" and as pointed out by Gizmodo, Power Nap is similar to Intel's Smart Connect technology, which works in much the same way.
A description from Intel concerning Smart Connect sounds awfully similar to the Power Nap description:
With Intel Smart Connect Technology in your Ultrabook, your email, favorite apps, and social networks are continually and automatically updated even when the system is asleep. No more waiting for the latest world news or friends’ updates to be delivered—just lift the lid and you’re up-to-date and ready to go.
According to Ryan Block over at gdgt, who's attending WWDC, a quote from Craig Federighi reveals something similar, "We all love using our Macs, but wouldn’t it be great if when we weren’t using them they were still working for us? Power Nap keeps your Mac up to date while it sleeps... It automatically refreshes data, it’s totally silent, goes easy on your battery, and it’s compatible with recent MacBook Airs and our new MacBook Pro with Retina Display."
For the "set it and forget it" crowd, such an application sounds like it would be quite useful.