"The director of" is misleading, it is a director (there are at least two higher positions: VP and SVP).
I'll take your word for it about Kurzweil. The wiki also says "a director" - good catch.
Here's what google says about Norvig though: http://research.google.com/pubs/author205.html
FWIW, I don't think reporting to higher ups (e.g. VP, SVP) precludes someone from being "the director" if there are no other people in the department with this title / position.
But yeah, Norvig is probably a little bit more than "a" director :)