But look at God of War III!
And next year I don't think The Last Guardian will have any sort of 'online connectivity' but I'm inclined to believe that it could sell over 1 Mil unlike Team Ico's past games.
If you make it compelling and fantastic, there is no reason why people won't buy it. Look at Assassin's Creed and II.
Sure games like Assassin's Creed Brotherhood, Dead Space 2 and rumored inFamous 2 and Batman Arkham City, which were previously SP only games that now are getting MP or Co Op Treatments but as long as the Game is great stuff and compelling enough, a SP game alone will still sell.
Though I must admit, Alan Wake, Castlavania Lord of Shadows, Vanquish and Enslaved aren't helping my point here...








