Leopard Developer Application Technologies Overview
It briefly covers integrating your application with Time Machine, iChat, and Calendar Store. More interesting is the new Scripting Bridge. It’s a replacement for using AppleScript in your app to communicate with another app. The “Scripting Bridge uses native Cocoa data types, such as NSString and NSArray, requires far less code than using an NSAppleEventDescriptor, and runs more than twice as fast as a precompiled NSAppleScript”. An example is given for getting the current track name from iTunes.
NSString *currentTrackName = [[iTunes currentTrack] name];
As far as I know, the Scripting Bridge hasn’t been mentioned in any Leopard discussions. It appears the Bridge lets a developer write Cocoa, but paraphrasing the classes and commands in an application’s Scripting Dictionary. If so, this will be quite tedious for developers to implement. In practice, they’ll have to write an AppleScript to determine how an application’s Scripting Dictionary works. Then developers will have to translate the AppleScript into the equivalent Cocoa code. It would have been nice if Apple could have provided practical information how developers will work with the Scripting Bridge. As well, the example given only demos the Scripting Bridge getting data from an application. But does the Scripting Bridge work both ways? Will it also send data to another application, and does it provide for the receiving application transforming the data and returning the result to your application? If the Scripting Bridge is two-way then the benefits gained by using it will far outweigh the mucking around us developers have to do with NSAppleScript and friends.
The article also mentions Core Animation and 64/32-bit hardware support, but these are treated too briefly to get an idea of how they might be used in an application.