Cappuccino is a re-implementation of Cocoa for Objective-J. They’ve provided most of AppKit, many widgets, the event system, and more. The “NS” prefix common to Cocoa libraries, inherited from the NeXTSTEP days, is replaced by a “CP” prefix.
The speaker cautions that using Cap is very much an investment in “Cocoa-land”, and that the framework is new, incomplete, and complex. “We’re not very good API designers,” he says by way of explanation for borrowing so much from Apple. “We’re starting with the desktop. […] It’s a mistake to discount all the lessons of the GUI world.”
Another demo: a Twitter client (woo). It’s not a lot of code, and we get a quick tour of it. Sadly, the demo doesn’t work.