It absolutely is, but "in active development" is to me another word for useless. SproutCore has been in production as MobileMe for three years and it still has

It absolutely is, but "in active development" is to me another word for useless. SproutCore has been in production as MobileMe for three years and it still has difficult bugs. Let's see some source code, or implementation details - something worth talking about. All the page has right now are pretty words and broken demos. And FWIW an implementation in nodejs isn't useful to most people. It's a cool proof of concept, but since nodejs isn't an everyday environment for web development, popularity will come by way of a clone in ruby or python.