There is no difference between crysis in dx9 and dx10.
Some of the higher settings were locked out at first but eventually through config editing people managed to make it identical. Now, of course, there was a difference between dx9 and dx10 in general. A newer API allowed for easier engine development, but the fact remains that for the end user the difference was simply not noticeable.
You see, for people like us, ie consumers, DirectX 11 as it stands now is about 90% marketing scheme. Yes, again, the API is way improved and will cause far less trouble in development, but the only result that we would get to witness other than the supposed performance increase is tessellation, a very old technology that has even been introduced to online rendering by ATI a couple years back, by the name of N-patches; it didn't catch on, sadly.
Dx11 is something those companies use to make you buy new cards. Graphics really have reached a point where a lot of people just don't feel the need to upgrade, so those marketing guys try to use Dx11 to motivate you to go and buy new hardware, with the promise of exclusive improvements. Sure enough, the new hardware that's coming out right now is way more powerful than anything released during the heyday of Dx9, and you will get better performance out of anything, but the performance increase has very little to do with whatever your version of DirectX is.
So to draw a conclusion:
DirectX 11 will not make the game prettier, and it will not make the game run better, Crytek could have easily developed the game just for the new APIs but have chosen to bear the difficulties of 9.0c instead to deliver a product that is equally compatible to anyone.
At least that's how it seems now, EA was also in charge of DA2 and that game was a really horrible example of shoehorning the dx11 gimmicks without polishing them out. But for now, I'm thankful, and you should be too.