The Washington Post Company will launch a new Web site on Monday dedicated to black culture and heritage. It is called “The Root” and aims to raise the profile of black voices in mainstream media. Harvard Professor Henry Louis Gates Jr., former New York Times reporter Lynette Clemetson, Terence Samuel of AOL Black Voices, Malcolm Gladwell, Thelma Golden, William Julius Wilson, John McWhorter, Charlayne Hunter Gault, and other prominent figures are joining in the project. The site will go live at 12:01 a.m. ET on Jan. 28 at TheRoot.com.