I think MacDonald's switching from "I'm lovin' it" to "Your inner child" and it's being spearheaded by this ad from the excellent Australian design agency Collider. It's one of those ads that will make you smile inside. Very very well done.

View the ad here, helps if you have quicktime already installed.
http://www.collider.com.au/webclips/mcd_large.html

A pity that the food is still a little crappy and over-priced.