Apple recently updated iWork and removed a whole bunch of features. The company where I work makes a popular Mac application, and the removal of AppleScript from iWork caused a backlash from customers who rely on this feature for integration between our program, and Pages and Numbers.
AppleScript wasn't ideal, but it did the job. Now we're left in the dark, and as Apple are being typically opaque about adding it back we're not sure what to do. The way it worked before was with scripting bridge, and although
SBApplication is still around, Pages and Numbers no longer have it.
Scripting Bridge provides an Objective-C API for sending and receiving Apple events, so you can take control of applications in Objective-C. It can be used to bridge another scripting language. JSTalk is one such example:
When we wrote AppleScript in the past we wanted to modify a document without having to understand how to parse its format. There's an element of driving the application, but also handling an abstracted version of the document rather than the underlying proprietary format. It's probably easier to say "make words that match this regular expression bold" than it is to write a parser for Pages documents.