Even more on the importance of novelty, this time from FOP Adam Lawrence.
Surprise and humor are intrinsically related (my Just For Laughs days provided a profound heritage, I guess), and as per this info, the former trumps the latter in the world of marketing and sales. As Adam puts it:
"In other words, humor is most effective from a staid brand; products with a rep for humor will need to up the ante or switch tack."
Being funny is not as important as whether you're expected to be funny. That's the explanation in a nutshell; here's the cognitive psychology post in its entirety. Fascinating.