Or rather, it returns a new function that wraps call/apply with a "baked in" value of 'this', so that it can be passed as a callback and retain the correct 'this'. That's a bit different than just being a wrapper for them - it's shorthand for using something like "var that = this" and a closure.

When we start seeing people using (jQuery.proxy(xxx)()) - then they've learned too much jQuery and not enough Javascript :-)