Thank you, Obyno, for letting me know about this. I had blogged about the nominations a couple of months ago.
The Man Booker Prize is a biennial event awarded to a write for a body of work. Achebe is the second winner of the prize.
This is the second win of a prominent literary award by a Nigerian writer in as many weeks. The Nigerian literary scene is seeing such a revival at the moment and wins like this will hopefully serve to encourage aspiring writers (and I know more than a handful myself).
BBC: Nigerian author wins Booker honour
Man Booker: Press Release