This reminds me vaguely of what Coffeescript does for Javascript (<a href="http://jashkenas.github.com/coffee-script/" rel="nofollow">http://jashkenas.github.com/coffee-script/</a>). It's a nicer, more modern syntax than the underlying language.<p>The killer is that they both require a compile to make it usable by a web browser. It would be far nicer if the compilers were written in JS and processed the languages dynamically.<p>The final compile before deployment can still happen via command-line tool, but this lets developers work in a simple edit-save-refresh environment.