If you are an adult who enjoys all types of humor (including the type that would make many people blush) and doesn't mind a little comic book violence in the name of "reality," you should probably go see Deadpool. If you think there are off-limits topics when it comes to humor, or you have a low tolerance for seeing others in pain, you should skip this addition to the Marvel Universe and wait for the next PG-13 installment.
Jesus and I saw Deadpool for Valentine's Day. It was a nontraditional choice, but that's how we roll. And despite its themes of justice/vengeance, spite, and combat (both verbal and physical), it was surprisingly tender during a few key moments. One could call it a love story with a grisly telling, or an action movie with heart. Heart and other body parts.
This green band trailer gets at the gist of the story (dude gets sick, needs a secret operation to stay alive but it also turns him "super" and super ugly (except not really, he's still Ryan Reynolds), he does it for the good of his relationship but afterwards realizes he should mess up a few bad guys since he can and because of what the operation did to him, his relationship is strained as a result of the operation and its effects on him, there's some death and destruction and comedic relief, a few X-Men show up, and upcoming movies are hinted at) ...BUT if you want a trailer that's more true to the mood and effect of the actual movie, I recommend checking out the red band trailer (NSFW).