Wow that's crazy. I saw your comment and thought "no way." I'm not the most tied into open source development but it is very surprising to me that something that is so embedded inside Rails is not being actively developed. I wonder if Rails is going to move away from it now as it probably should anyway?
This is such a bummer to me. I was a late-comer to CoffeeScript (just joined a project at a company that's been using it for years), and I absolutely love it. I was really skeptical ("JavaScript works just fine! Why change the syntax for no reason?"), but it's so slick.