What your seeing is the 'model' effect, the E3-2005 was polished. Whereas this footage is just straight from the game, it hasn't had a full polish yet. So lighting and shadows aren't just right yet. Its the same as taking a photo of a super-model whose just woke up and grabbing a coffee versus a photo-shoot with proper lighting...
As for differences?? Well the new army screenshot is meant to be dof'ed like that its an opening shot. whereas the E3-2005 shots you've shown are closer, so you can see the peeps better. A similar camera would produce a similar result with the new stuff...
There really isn't any major downgrade... its fundementally the same renderer just improved and made PS3 friendly. And better shaders, lots of better shaders now.
another reason why i love this forum so much! i must have vastly underestimated heavenly sword before hearing this.