"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
AirPods and AirPower: Everything We Know
Panther 'Test' Software Update
This Panther Update is being made available to test the Software Update feature in Panther and address a few Expos, Mail and iChat issues. Please install this update and provide us feedback via your normal channels
Screenshot [PDF]. Panther is still a developer's only release, but Apple appears to be making at least some updates.