Dion Almaer sums my feelings also on Closure.  As with all libraries, parts of closure are well baked, other’s aren’t.  I’m glad Google is sharing.

JavaScript over the long run needs to become more like Ruby or Python - there are hundreds of libraries that each do one specific thing really well.  Developers mix and match all the time, to get whatever happens to work best on their particular app.

This is why I think a module system like CommonJS is important.  It is also why we have continued to refactor SproutCore into smaller pieces that can be used on their own.

Now that we have learned how to build fast, large scale apps, we need to make these advances available in a way that you can adopt piecemeal as your app evolves.