"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
AirPods and AirPower: Everything We Know
Apple Seeds First Version of Mac OS X 10.5.4 to Developers
This release comes only days head of Apple's Worldwide Developer's Conference which is rumored to introduce us to Mac OS X 10.6 (Snow Leopard), Apple's next major Mac OS X version. As typical, Apple will continue to work on bug fixes on the current version of Mac OS X while the new version is readied. There is no known timeframe for the 10.5.4 release but Apple can wait months between these maintenance releases.