I am experiencing the same load checkpoint causes Crysis 2 to crash problem. So now I have to continue a mission by replaying it from start (which is pretty annoying). I don't have the stuttering problem though even with everything on Ultra with Hi-Res and DX11 enabled. My spec. are as follows:

Intel C2D E8400 @ 3.0Ghz
DDR2-800 4GB RAM
MSI GTX 460 1GB Cyclone in 2-way SLI (using driver 275.33)
eVGA 750i FTW motherboard
Corsair H850W PSU
Windows 7 x64 Ultimate English
Crysis 2 1.9 w/ Hi-Res and DX11 pack

Copy of game is legit.

...many other people have this issue. Hope they fix asap...

Having the save game issue as well.
Core 2 duo
GTX 560
4gb Ram

Please post your vram in addition to your card and clock. (2xgtx460 768mb). Running afterburner to track vram usage is enlightening.

Since 1.9, stuttering and lag for me is directly related to overloaded graphics memory, with or without groovy features enabled. As a quick and dirty fix, disabling AF in control panel works immediately, until the start of the next match....

Sorry was kinda lazy with my 1st post
Win7 64bit
C2D E8400 3GHz
GTX 560 1GB (have used factory default clocks and OC no differences)