There are a lot of fair points here, but I know personally for me that I was using jQuery for a lot of websites, then saw the beauty of some .coffee files and got into it. Since then, I've cared more about just plain ol' JavaScript and have stopped using frameworks (most of the time).

So while the syntax of CoffeeScript may mean giving up on the syntax of JavaScript, it's brought me closer to vanilla JavaScript and made me more aware of it, without being in the context of a framework like jQuery or Prototype.

Just my two cents...