No there doesnt seem to be a whole lot of difference between the 2 modes..
I would guess the parallax mapping is what makes the cliff face a bit different (normal map on SM1.1 perhaps? or bumpmap) and how the light falls onto it..
Geometricly its prolly pretty flat and lowpoly...
Demirug wrote some about why the modes are so similar and why there is no SM2.0 over at the thread on Rage3d..
The HDR is nice, its not as pronounced as in farcry without the autoexposure feature FC uses, but its neat..
could prolly get pretty close to the "HDR look" by just raising contrast and fiddling with settings like that tho, as it is now..
Altho I havent really looked into it too much, but it seems it "only" makes things a bit more colorful and with more contrast..
another set of comparisons.
SM3.0 (no HDR)
The HDR seems to do more then I thought to the overall image, not only in the more extreme light situations..
Comparing Sams suit on the SM1.1 and SM3.0 it seems more accurately lit on the later, brick wall is slightly more pronounced on SM3.0 and shadows are softer..
Things you prolly wouldnt notice without looking for it or doing a side by side comparison, they did a pretty good job with the SM1.1 path.
EDIT: almost forgot, screens are without AA, but downsampled to 1024 from 1280, so they may seem slightly SSAAed..