I don't know if I would count tessellation out so fast for the PC. While, like you said, Crytek isn't going to do anything majorly different for the consoles and the PC - I can't see the point of DX11 otherwise.
Look at this interview here:
Crytek head says:
|“If it runs okay on PC, but not 360 and PS3 yet,” said Yerli, ... “we don’t do it.”|