I'm not sure entirely why, but this movie is kind of a guilty pleasure for me. Almost every part of this movie just hit's me in the "Fun Zone" of my brain. It's silly, and it's stupid but it's done in a smart way, if that makes sense to anyone but me. The timed gag's were something that I really dug - even the musical elements (something which usually I don't find very entertaining in movies) work for me.
I'd say go into it with an open mind, and don't over think anything and you might have a good time watching this.
But then again, there just might be something wrong with me.