"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
AirPods and AirPower: Everything We Know
Apple Releases Safari 3.1.1, Addresses PWN2OWN Vulnerability
This update is recommended for all Safari users and includes improvements to stability, compatibility and security.
Most significantly, Apple notes that 4 security issues have been patched in the release, one of which was recently used to successfully attack a MacBook Air in the CanSecWest PWN2OWN contest.