Cocoa Core Data

When Apple introduced the binding controllers in Panther (Mac OS 10.3) they eliminated a lot of the glue code people used to write to keep the model and view of their applications in sync. Now they're aiming to make the persistence of the model simple too with Core Data, a new framework in Tiger (Mac OS 10.4). This article on Apple's Developer Connection website explains it with a bit more detail. While it somewhat resembles Object Relational mapping it looks to be a file based persistence mechanism. The developers of Delicious Library had good things to say about Cocoa Bindings:

We rewrote everything in a day or two—I think we deleted over a thousand lines of code that just wasn’t needed any more.

...so I'm hoping that Core Data will be equally well received and productive.