Coding Strategist

In this video Matt Cutts says ‘This is a piece of script written in PHP sort of stuff’ while pointing at something that is clearly JavaScript.
Just click the play button in the video below to hear him say PHP where it should have been JavaScript.

How can someone who joined Google in 2000 as a software engineer make such a mistake? This mistake suggests that Cutts does not know the difference between server side and client side scripting. Is he just a good actor who does geeky PR for Google or was it a slip of the tongue?