Hmm thanks guys I'm of mixed opinion.
The Witcher demonstrates a very unique set of natural environments. Perhaps it's the specific colour palette of the flora, or the glittering overcast thunderous skies which are wonderfully striking that seem to be reminiscent of the Scottish and Welsh landscapes. The late summer evening feel in the landscape above has an almost palatable feel of dread, a calm and beautiful sunset is often considered to be ian dylic setting, however in The Witcher's case, there is a creeping fear that something unpleasant is about to occur, akin to the opening of the horror film Jeepers Creepers 2, (in which a young boy is suddenly chased across a field by the Creepr, in what originally appeared as a tranquil field setting against a late summer sun.
There is something about The Witcher 1 in it's environment design and the 'feel' of the land that is really unique, it doesn't look like any other natural landscape out there in any game.
The Witcher 2 , demonstrates several extremely well designed elements of the natural environment. One of the the qualities that makes TW2 great is the changes in the standard weather cycle aren't just limited to large scale weather shifts but include the momentary fleeting shifts: i.e. watching the sunlight pouring through the overheard branches/clouds suddenly shift from intense sunlight to a dark overcast shadows mimicking the subtle winter/spring weather patterns we so often encounter as fleeting moments is wonderful, it's not immediately obvious which again adds to the atmosphere of the TW2.
The environmental flora is wonderfully detailed, rich and varied: small, medium/large flora is integrated around the natural environment in a much more believable manner, rock crevices are complete with plants, hanging moss from entrances to caves, the forest floor illuminated by the sunlight, scattered by the forest canopy is scattered with a variety of leaves in different stages of decay. The tree's in Flotsam Forest have thick gnarly gangly roots are almost stereotypical as they rise from the ground to form the large ancient trunks overhanging the cliffs and wonderfully twisted and organic terrain.
The terrain found in the TW2 environments i.e gullies, brooks and riverbanks are wonderfully crafted to form detailed almost textbook representations of natural geology: there is a great deal of attention to the game's terrain, demonstrating erosion, decay and related organic processes. The environment also lacks identifiable visual repetition, it's hard if not impossible to identify two identical tree's or rocks, the bane of any virtual environment with virtual assets that are often hand crafted , is that overuse can often lead to visual repetition, which can break the believability , and possibly immersion of a natural, organic setting.
The minor geological formations are also impressively visualised , harsh transitions (i.e lake beach and the forest) between landscape types has been almost removed through through detailed design i.e. the riverbanks in the game aren't uniform, it's long form is broken by irregular mounds of loose stone than blend the form with the surrounding geology.
TW2 does feel more clichéd in comparison to TW1, and almost like a Hollywood interpretation of an old B movie classic, but the natural environments, to me are simply stunning, probably the best I've seen in any game to date. TW1 wins on it's uniqueness and it's strange quality, TW2 wins on it's incredible rich and well implemented environment design.