I've seen television spots for something like a "Da Vinci Code Quest on Google." Have not seen anything on the bottom of the SERPs as yet.
But, if I search for Da Vinci [google.com], up pops a Google sponsored Adword for the contest in the sweet spot (wonder how they managed that?), a "New! Crack the Code" teaser (guess they aren't too sure of the power of the Adword ad just above it), and a one box to find a theater.
Now I got it. If you search for something related to Da Vinci the promo stuff shows up top. Non-related as MB pointed out it runs at the bottom of the SERPs. It's unobtrusive enough that I didn't notice it at all today until Roger posted about it.