Have to re-watch it as I was working on some deals while it was on, but from what I saw it looked good. It came off realistically, tough to do given the subject matter. From the season preview teaser at the end, it looks like it's going to get REALLY interesting (like when the reporter brings up that he was essentially fired that morning, so is he even a legitimate President?), and the unfolding of what appears to be a domestic conspiracy but that could be a misdirection. Also, the FBI woman's boyfriend will probably turn out to be involved in the bombing, or at least among the dead at the scene.
Keifer's acting in this is basically "Jack Bauer neutered", but he pulls it off. I imagine that he becomes more action-oriented once the situation becomes more clear, which will be fun.
I hope it lasts, I'm intrigued.
One funny note: was talking to two moms last night at my son's Fall Ball practice (fall little league), and they were talking about 24 coming back. I joined in and was talking about looking forward to it, and then it became clear that the one who brought it up thought that this show was the 24 reboot ("it has a different name"). Pretty funny.
EDIT: Forgot about this - at 9:36 PM, during Blackish, ABC showed a graphic for this show that read "In 24 Minutes". Thought that was clever.