I watched a couple of videos including the video above and it seems like a lot of running around with no action.
barmy's testimony seems to support that.
=/
Not sure about lack of action as on my second mission it lasted ages and I had hordes of enemies spawning and attacking me. It pays to explore the levels, smash everything for loot and hack terminals, open vaults/rooms as there's a lot of shiny stuff to obtain for crafting/upgrade your gear. I'm really enjoying it and the combat is great plus Loki+Stealth is brilliant.
Co-op is good IF the players your with stick together but when you get a rambo in the group running off and triggering everything the missions don't last. I reckon you'll get the most out of this if played with a good group of friends and not randoms.
It's definitely worth the 1gig download to try out, so far it's above average for sure.