Indeed he is, according to this in The Hollywood Reporter:
Terrence Howard ("Iron Man") is to portray Nelson Mandela in the Jennifer Hudson-starring feature "Winnie," based on the story of Winnie Mandela, Nelson Mandela's former wife.
Darrell Roodt is directing the $15 million historical drama, a South Africa-Canada co-production set to start production May 31 in Cape Town, Johannesburg and Robben Island, where Nelson Mandela was held prisoner for 18 years.
Also Friday, Canadian distributor D Films said it acquired the Canadian rights to "Winnie," a co-production of Canadian producer Equinoxe Films and South African partner MaAfrika Films.
Toronto-based D Films recently picked up a second Equinoxe title, the $6.4 million film "A Million Colors," another Canada-South African production directed and co-written by Montreal-born and New York City-based Peter Bishai.