Singleplayer campaign is short, five or six hours some probably longer if you stop to look at every nut and bolt in the game.
Despite the fact that Crytek put in a hard coded graphics card DX11 check you can disable all the features that DX11 brings - and it seems most people are if for no other reason to make the game look better by turning off post processing fx, if it weren't for that stupid check I would have bought the game.
I'm not on the warpath for a new graphics card just yet.
edit: yep, final code of the game. seems that another complaint is the number of night/dark maps outnumber the daylight ones. perhaps they did that to conceal the rough edges when played on consoles.