I had guessed that Obama chose her on account of the strong American historical grounding of her poems--I've read her book AMERICAN SUBLIME, which has a whole section revolving around the Amistad slave ship rebellion, and other poems also engage historical subjects. But according to the Washington Post, she was a friend and neighbor of the Obamas in Chicago, and her father was a former Secretary of the Army and attorney in the Kennedy administration--so there were other reasons beyond her solid poetic credentials to give her the nod (I was rooting for Yusef Komunyakaa or Natasha Trethewey, but think it was a wise choice). The same article also says that she was one year old and present in her baby carriage on the Washington Mall when Martin Luther King gave his famous "I Have a Dream" speech--what a fitting backstory to her inaugural appearance next month!
http://www.washingtonpost.com/wp-dyn...121702027.html