"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Adobe's Flash Player 10.2 to Offer Up to Ten-Fold Improvement in CPU Efficiency
Adobe MAX demo of Stage Video on MacBook Air
(audio and video slightly out-of-sync)
Nack points to a demo from last month's Adobe MAX conference showing off how Flash Player 10.2 and Stage Video can reduce CPU load. The demo shows a standard Flash video playing on Apple's new 11-inch MacBook Air checking in at about 80% CPU usage, and when vector images are overlaid on the video, CPU usage spikes to over 120%. The same video using the new Stage Video API demonstrates CPU utilization of about 10% with and without vector images overlaid.
The Stage Video implementation requires that Flash developers update their video players to support the feature, but some major developers such as YouTube have already updated their players, with others expected to do so in the near future.