What company (besides Treyarch and Infinity Ward) sticks to the same style game after game? Crytek, like most other developers, experiment with their style. Almost every developer does it. Dragon Age: Origins, you're a Grey Warden saving the world. Dragon Age 2, your a nobody protecting your family and rising to the top. You're in a pawn in a much bigger plot. Dragon Age 3. Bioware is taking the best of Origins and 2.
Take Halo for example. 1,2, & 3 were pretty much the same style/gameplay. Then comes along ODST and Reach, and their different. Halo 4? It will be different. Its the same thing Crytek is doing. Crysis came. Open world, blah blah. Then Crysis 2 came. And it was different. Now, Crysis 3 is a year away and because it has SOME similarities to C2, a lot of you are complaining.
Crytek is giving you the best of 1 and 2. Most of you (I guess all of you to be honest) enjoyed the open world of Crysis 1. Well, look. Crytek is doing their best to give you as much of that as they can to you in Crysis 3. Will it be anywhere near the level of open world-ness in Crysis 1? No, this is one of the down sides of developing for current generation consoles. Yes, it looks like Crysis 2. Of course it does. Crysis 2 looks different from Crysis 1 because an entire new game engine was used. That's not the case in Crysis 3. Their using the same engine as Crysis 2. Only this time its been updated some.
A lot of you are complaining that 2 years is not enough time for development. I think I can explain this best with an example of Assassin's Creed. Assassin's Creed is/was (can't be sure after 3 comes out) a yearly release game. But Ubisoft was almost simultaneously working on each release. Its the same case with Crysis 3. Crytek confirmed the story was done when Crysis was just released. This obviously means they started working on Crysis 3 when the story for Crysis 2 was done, which puts the development time at least 3 years. You guys should be happy Crytek doesn't make Crysis 3 a console exclusive because of YOUR piracy rates.
Long rant post but too many of you (a lot of you being pc gamers) complain about how Crysis 3 looks like Crysis 2/2.5, how it'll be the same, blah blah, when there's obvious reasons for each complaint. People really DON'T like change. (Guess that's why so many of us like COD)