Square Enix’s Thief 4 announcement has leaked via a Russian website, along with the first screenshots. The game is in development at Eidos Montreal, coming in 2014 on PC and next-gen consoles.
UPDATE: Thief has been officially announced via Game Informer. The series hero “Garrett returns to the Gothic, industrial metropolis known simply as the City to steal any and everything that will make him richer”.
“Unfortunately, the City is broiling with social tension as it is ravaged by a plague and lorded over by a political tyrant known as the Baron. In order to survive his adventures, Garrett will have to pay attention to his environment and make use of the may possible paths through each of the game’s levels”.