Correct, I see a lot of us are thinking the same thing. I literally fell out of my seat laughing the first time I saw Blazing Saddles! Another that is great is the first Austin Powers movie.
Blazing saddles is almost as good as airplane — I think they got the #1 right. However, as someone else posted, how My Cousin Vinny is not on this list is beyond me — that is one of the funniest movies ever. The prison seen where they meet Vinny for the first time had me laughing so hard, I was crying...and the judge, Holy crap.