Common Sense Note
Parents need to know that this movie involves a great deal of comic-book violence executed with near-bloodless restraint but, at the same time, visceral efficiency. One character is a Holocaust survivor; there's much discussion about tolerance and hatred and prejudice, all in the film's fictional context of "mutants" with special abilities appearing in the human population -- and yet, this might provide a great conversation-starter for families.
Sexual
Content
Some kissing; a blue-skinned, scaled mutant shape-shifter is, essentially, walking about naked, albeit covered by scales and cartilage that make her slightly modest.
Violence
Largely bloodless violence, some of which involves good old-fashioned fisticuffs and stabbing, some of which involves superhuman abilities like a control of magnetism or the weather, or shooting force-beams from one's eyes. Many of the characters have invulnerability or fast-healing abilities that make their injuries sustainable. A young girl is stabbed accidentally by razor-sharp claws, but her abilities enable her to heal from her wounds. Scary, intense medical imagery. A human being liquefies.
Language
Light strong language, including "balls," "dick," "God," "damn," and "hell." A variation on the finger is given.
Social
Behavior
The film's messages -- that peaceful co-existence is preferable to conflict, that tolerance is preferable to prejudice, that being different is not in any way bad -- are intrinsic to the film's plot and themes.
Consumerism
Tie-in to vast quantities of related merchandise. Some light product placement (Oakley Sunglasses, Mazda), but no mentions of brands.
Drugs / Tobacco /
Alcohol
A character smokes cigars -- and is admonished for doing so. Beer and hard liquor are drunk.