Deadpool has never been a conventional comic book character, he breaks the fourth wall frequently (talking to the camera) and is a massive enthusiast of swear words.
So when Marvel announced that 20th Century Fox were making a stand alone Deadpool movie it was unsure if they'd do it properly, the studio is a huge fan of family friendly movies, and last time the character was in a movie they cocked it up badly (X-Men Origins: Wolverine).
Don't worry though, Deadpool takes note of the studio's past mistakes as he narrates the trailer... for his own movie! Yes, that's correct. While Marvel come under a bit of scrutiny for effectively following the same formula for every movie, this looks set to throw the formula straight out the window.