I'll agree with many of the guidelines, but some are just personal taste. For instance, I like to indent my JS with 4 spaces and so does Douglas Crockford (http://javascript.crockford.com/code.html)
I prefer to emulate the prevailing standard of my server side language when it comes to indentation, so when I'm working with PHP in the back end it's 4 space when I'm working with Ruby it's 2.
