There's little more popular in comic books than team-ups between its most famous figures. Just think about the success of The Avengers films. Deadpool is notorious for teaming up with (and generally irritating the hell out of) some of Marvel's greatest characters. His little exclamation of "Yay!" at the thought of pairing up with Spider-Man is a little nod to the excitement fans feel when these team-ups occur. Plus, of course, he's referencing Spider-Man's famous "Spidey sense" power...