Reading a quick description of Day One and seeing this behind the scenes footage, I think this might be NBC's version of Jericho. That's probably the show that this will be compared to, though this one looks more action-oriented. It's from ex-Heroes/Lost/Alias writer/producer Jesse Alexander, and it's about a group of people from an apartment complex in Van Nuys that have to band together when something mysterious happens to the planet.

(S07E02) "What the hell happened to you?" - Jack

Two hours in and I've gotta say - this might be the best ensemble cast that 24 has had yet. Cherry Jones and Colm Feore are just great as the President and First Gentleman. Annie Wersching and Jeffrey Nordling are doing awesome filling the void that CTU has left, and on top of all that, Carlos Bernard is back. It's shaping up to be a pretty good season of 24.