Coffescript is really nice. We migrated a 3k javascript app to a 2.5k coffeescript one (lots of it automatically with an app specific script). We gained performance, we are much happier with our gui code now. Proper classes, generators, terser closures, ruby-like removal of inferable parenthesis, and lack of ';' is a big win.
It's nice to hear that CoffeeScript is nearing a 1.0 release very soon now. Not that the API changes all too often, but a 1.0 release signals that the language is ready for prime-time to both developers and to book publishers.
I tried to move to Backbone.js but I'm not sure I like the style of coding it advocates. I ended up moving to KnockoutJS. I find knockout's data-binding and dependency tracking more elegant. For instance:
<div data-bind = "style: color: color">Colored text</div>
class SideBar
color: ko.observable("white")
promptColor: ->
cssColor = prompt("Please enter a CSS color:")
@color(cssColor)
sidebar = new SideBar()
ko.applyBindings(sidebar, document.body)
sidebar.promptColor()
This style works pretty well, even as the app becomes large. With backbone I was less sure where to put things and the syntax tended to be more verbose.
