I'm pretty sure that Irrational purposely got our hopes down. It starts underwater, with music playing. Then it shows it's not just BioShock 3, as it's in a new city. Then as the press begins to release their previews, it's shown that the ties to the Rapture BioShocks are minimal if not none, as Ryan would not yet be born (As it takes place in 1912, also changing the aesthetic and tone more), and the game is void of Plasmids. The new city, Columbia, was not created by people who resented the government, but the government itself, as an attempt to show the rest of the world that America was a real player in the world market, which it was trying to do in the real world at the time that Columbia was created in the BioShock one. So ya, this ain't just BioShock 3 in the sky.