Did CNN alter/darken pictures of Soledad O'Brian used in ads for its series "Black in America"?

It appears in some of the promo ads being run on the CNN web site show O'Brian as darker complexioned. Ms. O'Brian - a respected and popular reporter - has a very ethnically diverse background but most people would likely note her appearance mostly reflects her Latino (Cuban) background more than her African ancestry. I have wondered if CNN was darkening her pictures in the ads to make her appear more African-American. I realize it's cynical but the big media companies often make me wary of their motives.