The Obamas were loaned a selection of art from Washington area museums, including this piece by Glenn Ligon:

BlackLikeMe_GlennLigon

Glenn Ligon, Black Like Me #2, 1992, paint stick and acrylic gesso on canvas

See the New York Times slideshow since there doesn’t seem to be a large image available.

Update: here’s a larger image of a similar piece:

glennligonzora

Glenn Ligon Untitled (I Do Not Always Feel Colored), 1990