Looks like Apple is really putting a lot of dynamic language hopes into this project. When I talked with Ted Goldstein, then head of Apple developer tools, at

Looks like Apple is really putting a lot of dynamic language hopes into this project. When I talked with Ted Goldstein, then head of Apple developer tools, at WWDC a few years back (he happened to sit at my lunch table), he said their eventual goal for Objective-C was a full, Smalltalk-like runtime IDE. (Ted was at PARC for many years, working on Smalltalk.) And they're clearly getting there, slowly but surely. (LLVM is key to those plans.) But MacRuby promises a shorter path to a dynamic language completely integrated with the Objective-C runtime environment. Quite interesting to watch. Another good point he made was that MS still isn't using C# for any of their built-in or system applications, while Apple is using Objective-C/Cocoa for all of their major apps. (Well, except for a few Carbon laggards like their audio/video high-end apps.) That told him Apple was doing something right. In that vein, he also noted that people looking in from the outside would never "get" the power of Objective-C/Cocoa (which is just "Smalltalk in C" with a fantastic runtime library)--the language is just off-putting enough at first glance that people don't understand--, and that made it a good secret weapon.