Yes I can confirm this as well. Lowering the settings from Very High to High, Medium or even Low does not offer a significant FPS boost like it should. All it does for me is decrease visual quality and lessen the stuttering. I just checked a few minutes ago and I got only 4 FPS boost from Very high to Medium. Though the stuttering was greatly reduced.
I watched the livestream where Dan mentioned that they would probably have to sacrifice visual quality in order to get the game to run faster and considering the fact that it is also being developed for consoles, I think some sacrifices will be made for those platforms even after the game is optimised properly. I doubt that the consoles will be able to run the game at anything higher than Medium-High but I really hope that for the PC version, we get an optimised version PLUS the option to enable the FPS killing options, should we desire to when we get better hardware, just like Crytek let us do with the original Crysis.