The MacBook Air's exterior design is largely unchanged from the unibody design of the previous model. It still boasts 1 Thunderbolt port and two USB 3 ports, but now features dual microphones, where the previous model only had one.
One clever power management trick is the ability to wake up from standby in just 1 second and run on standby for 30 days. Actual usage battery life for the 11-inch goes from 5 hours to 9 hours. The 13-inch MacBook Air goes from 7 hours up to 12 hours or battery life.
The Wi-Fi antenna has been upgraded to 802.11ac, which is up to a claimed 3x faster than the 802.11n wireless receiver in the current model. To take advantage of that additional speed, Apple is also releasing new Airport stations as well.