It was the same level as during the E3 playthrough, but it played out completely different. The stair was collapsed, so they had to find an other way up. First Joel gave Ellie a boost to get on some crates on which there was a ladder. She pushed the ladder down and Joel used it to get on a higher floor. Then they went to the roof where the bad guys could be heared like in the E3 demo, but instead of going through the window and schooting the guy, Joel took out an empty bottle and trew it through a window to distract the guys. They then quickly jumped through an other window and moved past the guys. In an other room, there was a guy searching some drawers, which Joel snuck behind and took in a chokehold while aiming his gun (4 bullets) at the guy's head. It looked incredibly realistic, with the bad guy nearly pissing his pants and Joel whispering "not one word...". He dragged him to the room next door, while he choked the guy to death.
They then moved on to the next floor by climbing some rubble (i think) through a collapsed ceiling, where they found some corpses in a badtub and a lead pipe (which joel picked up and attached to his backpack). In the hallway, they heard some bad guys that were ordered to split up and search the rooms. Joel grabbed a brick (from his backpack I think) and rushed to the only guy that was left behind and brutally bashed his head in. The other guys nextdoor heard it and a firefight started. The guy who was playing killed one of the baddies with a headshot, but most of his other shots missed, so he quickly ran out of ammo. One of the baddies snuck behind joel and started to smash his head on the cupboard he was hiding behind. The badguy than took Joel in a chokehold and dragged him in the open, shouting "SHOOT HIM" at another enemy, to which he replied "HOLD HIM STILL". Joel managed to free himself by elbowstomping the guy in the stomach and used the guy as a schield, just when the other enemy took a shot. What then happened was that the remaining enemy started running away while joel was chasing him. It was very tense, with Joel panting and checking behind every corner, until the guy showed up in the hallway behind him and threw a molotov at him (barely missing Joel and hitting the wall next to him). The guy then came charging at Joel, who shot him in the elbow and then in the head (with bullets he found after he took out the earlier guys). He then started shouting for Ellie, who was hiding during the gunfight earlier and was left behind during the chase. She answered that she was fine wile she came running down the hallway, and she was schocked when she saw the body of the guy who's head was half blown of. At the end of the demo, they climbed in a lift shaft and Joel gave Ellie a boost to reach a higher place, after which the lift came crashing down with Joel still on it. Luckily, the floor was flooded, so he landed in the water. He shouted at Ellie to ask if she's ok, to which she replied that of course she's not ok, because he scared the shit out of her. She wanted to climb down but Joel forbid her and said he would find a way up. He put on his flashlight and started walking down the flooded hall.
And that was the end of the demo. I'm sure I forgot some details but you had to be there to believe how amazing everything looked. The UI was almost non-existant which made it look like a movie at times. Ellie and Joel were constantly talking to each other during the calm parts and some parts (like the badtub and a poster) had a yellow glow with which you could interact to hear some banter. When entering an empty room, Joel would tell Ellie to look around to see if she can find something (like bandages and ammo, or stuff to progress through the level). What amazed me the most where the facial expressions and the level of detail. For example, after Joel got his had bashed to the cubboard, a big bleeding wound was visible on his nose that stayed that way for the rest of the demo. I really hope all of this was actual gameplay and not some fake presentation, because all of this looks almost to good to be true. But there was a guy playing with a controller in the front and he did miss some shots (and even put the demo on pause at the end to restart from checkpoint) so it probably was a real playthrough.