Heh. That was awesome.
Not so fond on the guys with goggles welding stuff, though. Somehow it looks too modern.
I think that was the idea. When you first see them, you have no idea it's a film set in the future. And I thought it gave the whole proceedings a magical air, like Lantern Wastes in "The Lion the Witch and the Wardrobe" or all the steampunk tech in "The Golden Compass." Sure it's anachronistic, but that's the whole point. Made for a very effective teaser, IMO.
Now, if this sequence is in the final film, that'll be a whole other story...