I probably will be let down by this, it would not be the first time. Rewatching the demo makes the me think the path he took was a little too slick and scripted. I got hyped and then disappointed by the following games this gen:
Bioshock - Promoted as a morally gray free-roaming shooter with interesting enemies, situations and weapons. Turned out to be a good linear FPS with a couple of cool tricks that storywise ran on too long.
Asassin's Creed - Promoted as a gorgeous gigantic Sandbox game in a unique setting. Turned out to be empty and repetitive.
Alan Wake - Promoted as an amazing supernatural mystery game with tons of style set in a fantastic little Pacific Northwest town. Turned out to be 75% running around in the woods shooting the same pseudo zombies over and over while your flashlight ran out of batteries. The combat was so repetitive it felt like a bad rail shooter in parts.
I'm basically with you. Bioshock had an amazing initial E3 reveal that turned out to way oversell the game. It did not feel significantly more sophisticated than Doom 3 to me, and the fact that you were in an underwater city didn't really matter.
Alan Wake I liked for what it was, but compared to the initial teases, it did indeed feel like a corridor shooter.
Assassin's Creed I think got a lot better by the time it got to Brotherhood, but the improvements basically made it into a weird action-RPG/collect-a-thon. It has very little to do with being a stealthy assassin or strategically maneuvering through the environment.
I was impressed by the Watchdog demo, even though a lot of it is obviously scripted, until it hit the shooting part. Clearly that is going to be 50% or more of the game according to the current fashion. If they promised this game would have no guns, then it would be one of the most interesting announcements in years.