"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Mac OS X 10.3.6 Update Now Available
The 10.3.6 Update delivers enhanced functionality and improved reliability for Mac OS X v10.3 "Panther" and is recommended for all users.
Key enhancements include:
improved file sharing for Mac (AFP), UNIX (NFS) and PC (SMB/CIFS) networks
more reliable network automounts and launch of network applications
improved OpenGL technology and updated ATI and NVIDIA graphic drivers
additional FireWire audio and USB device compatibility
updated Calculator, DVD Player, Image Capture, and Safari applications
improved compatibility for third party applications
previous standalone security updates
For detailed information on this Update, please visit this website: http://www.info.apple.com/kbnum/n300080
For detailed information on Security Updates, please visit this website: http://www.info.apple.com/kbnum/n61798