"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
AirPods and AirPower: Everything We Know
3d Interfaces for Leopard?
The article is self-described as "wild speculation" so no specific inside knowledge is claimed. The author imagines:
We've already seen the iPhone seamlessly zoom in, zoom out, and flip icons, windows, and screens. Think about what a real computer could do here. Cover flow and multi-party iChat video show a glimpse of what a 3D accelerated user interface could look like, with light sources, reflections, and more.
While this is based in speculation, we have heard rumors that much of Apple's new Finder interface will take advantage of the new technologies in Leopard -- specifically Core Animation. Apple is already promoting the use of Core Animation in building better user interfaces. From a WWDC 2007 session titled "Building Animated Cocoa User Interfaces":
Delight your users with dynamic, responsive user interfaces. In Leopard, standard AppKit NSViews can be rendered and animated using Core Animation. Learn how to combine familiar Cocoa controls, views, and event handling with the power of Core Animation layers to create stunning user interfaces.
Apple is already using Core Animation in Leopard's Time Machine and details about Core Animation's capabilities are listed on their site.