Look at the timing of the dragon attacks, how the dragons fought, what the dragon attacked etc. Look, first you attack a mammoth, then a giant attacks you, then the dragon comes and kills the giant, then you fight the dragon with lots of random guards everywhere AND SO ON. Obviously Bethseda wanted to show-case their game, and this also obviously involved prettying up the gameplay.
Not to mention the quickness of the enemys' deaths. They died after 1-2 hits swords level 22.. lol. The dragons were brought down after a few spell attacks. The bandit reaction to one of his mates getting sniped seemed to be scripted as well.
Look at that random fox chasing that random rabbit by the road. 10 seconds into the trailer that happens. I can't be certain, but the chances of that happening are probably very slim in the actual game.
The character was obviously buffed /or enemies were nerfed. I also think the undead's AIs were funny.
just watch the entire thing again
BUT, guys, don't cry. Every gaming company scripts their demoes. And Bethseda is no exception.