We discussed this a bit in another thread and I think the consensus was that while MSAAed deferred rendering can be done on D3D10, the way that samples are queried would perhaps make it a bit less efficient than it could be (probably not quite as bad as super-sampling, but somewhere in between SSAA and MSAA certainly). I have no idea what D3D10.1 will bring to the party...
Interesting...maybe they're doing the cartoon outline as a post-process? Maybe some sort of edge filter (Sobel?) on the normal/depth information in the G-Buffer? I've seen an implementation that did something similar, except they used the results of the edge detection to do a selective blur.
i've not seen any evidence at all of real time ambient occlusion in stalker, i'm 99% certain that it will be baked. In fact the only place i've seen a hacky version of real time occlusion is in crysis.