My only qualm is that it gives advice on how to use arguments.callee, which was depreciated in ECMAScript 5, for recursive anonymous functions.

Since they already give an example of how to use a named function recursively, the arguments.callee example could just simply be removed.

No really it was last significantly edited in 2006. Look at the contents of the revisions for the past 3 1/2 years: https://developer.mozilla.org/index.php?title=en/JavaScript/...