jQuery .css() Performance (1.4.2 vs. 1.4.3)

jQuery .css() Performance (1.4.2 vs. 1.4.3)
Originally uploaded by John Resig

I like this. I really do. Every improvement to jQuery is a big win to my life as a web developer.

But....

Isn't it best to do your CSS in your .css? If you need to change a stylesheet thing, make a class and .addClass(myClass) to it?