To be fair, they do link to some JS conversion thing, but I'd prefer to read the examples right in the article - "don't make me think" and all that.
edit: Disclaimer: I have written and am still occasionally writing canvas rendering stuff in coffeescript and after some meddling around with some annoying bits it has been quite pleasant. For example you should make sure that functions that don't need to return anything, return false or null or undefined. Otherwise coffeescript will return whatever your last statement evaluates to. This is especially bad if the last thing is a loop.
These are the same problems from Actionscript (I know the crowd here has no love for AS though).
Not only should you consider using object pooling for JS objects (like the author describes), but you also want to think about DOM element pooling, especially when you are dealing with large lists.
The 'soft crash' would result in a situation where the app and overall runtime is still running but the state of the software is no longer reliable until you reboot the TV. And none of this stuff (the timed gc, etc) was documented at all, and there's little to no active community for "Yahoo Widgets" so you basically had to figure this all out on your own.