MacRuby is irrelevant
Apple clearly puts a lot of effort into making LLVM infrastructure and Objective-C a powerful general-purpose toolkit for themselves. If they miss some feature, they are more likely to add it to LLVM and/or ObjC rather than spinning off additional separate projects. They already have WebKit and JS and that covers a lot of what they want to do. And they are bold enough and smart enough to improve things in both technologies whenever they want or need to.
Forget about MacRuby, MacPython and other languages in that respect, they are clearly are only interesting to people who focus more on typing codes than on shipping products.