"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Apple Releases OS X 10.11.3 El Capitan With Multiple Bug Fixes
The OS X 10.11.3 update can be downloaded through the Software Update mechanism in the Mac App Store. It is available to all OS X El Capitan users.
During the beta testing period, no significant outward-facing changes were discovered in OS X 10.11.3, with the update instead aiming to improve performance and fix bugs discovered since the launch of OS X 10.11.2. According to Apple's release notes, OS X 10.11.3 includes unspecified bug fixes and security updates.
The OS X El Capitan 10.11.3 update improves the stability, compatibility, and security of your Mac.OS X 10.11.3 will be followed by OS X 10.11.4, which is already in testing and has been provided to developers. Like OS X 10.11.3, OS X 10.11.4 appears to be focused on fixing bugs and improving performance rather than introducing new features. OS X 10.11.4 will likely see a spring debut alongside iOS 9.3.
This update contains bug fixes and security updates.