Open world games are extremely popular and high profile ones tend to be high sellers. Skyrim. and even Fallout. GTA and even Red Dead Redemption. Assassin's Creed and now evenFar Cry. And Watch Dogs joins teh ranks
I'm not talking about open world games in the style of Infamous or upcoming Sunset Overdrive.
I'm refering to those games which tend to allow for a greater level of exploration, since they don't allow the same fast paced traversal. IMO, if it got enough marketing and hype, a first/third person open world action game, with some potential RPG elements, could be a huge seller, and a great IP to help boost sales of either console.