Unfortunately, those pictures are kind of low-res and in lossy JPG. To my eye, the battle terrain looks vastly better, and some of the spell effects (like lightning) are very impressive compared to the lightning in Doms2 (which didn't look like lightning).
The low screen resolution and JPG compression artifacts make it difficult to get a good view of the units themselves, but they look higher-res than in Doms2. Maybe additional pictures will be released, higher-res and in lossless png format, that make the changes more obvious.
Bear in mind, though, that release date is "Summer" - and unlike Oblivion and Trespasser (whose graphics got monotonically worse with each new set of shots), I suspect Doms3 will only get better
Re: Updated graphics?
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