The Hollywood Reporter recently announced that Zoe Saldana was in negotiations to star as singer Nina Simone in the biopic 'Nina' as the titular biopic. There has been an increasing amount of online backlash over the fact, as many have stated that they don't think Saldana has the right looks to play Nina. More specifically, many are saying that they feel that Saldana was cast due to her lighter skin (whereas Simone had much darker skin), making her a more appealing choice for studios and in their views, audiences.
Not many (if anyone) are arguing with her acting skill, which everyone knows was well on display in 'Avatar'. However, one could easily argue that there are many other African American actresses (with and without darker skin) who would suit the role better, so why was Saldana chosen? There is a very easy answer to this: because she is one of the few African-American women in Hollywood (although she's technically bi-racial) with the best buzz in the business. After starring in Star Trek and Avatar, her international fame levels have shoot through the roof.
Everyone knows who Saldana is, and everyone likes. Whether her skin color has anything to do with that is highly doubtful, but rather her well-known roles and the fact that she is increasingly becoming more famous. In small budget movies like this, it's easier to get financing if you have the biggest name star attached and in this case, that would be Saldana. Of course, you could just as easily put Viola Davis in the role, but Davis is not as well known internationally.
Saldana, 34, first got her big break in 2000, with 'Center Stage'. After that, she has acted in a variety of supporting roles, ranging from 'Terminal' to 'Crossroads' to 'Pirates of the Caribbean: Curse of the Black Pearl'. However, she received her biggest break when simultaneously cast as Neyitri in James Cameron's global blockbuster 'Avatar' as well as 'Uhura' in Star Trek. Audiences will continue to see her in sequels to both films reprising her character.