Just watched the pilot last night.
I didn't really like the first ten minutes, and when the lead girl admitted to her superiors that she was a "bitch," I almost turned it off because she seemed more like a wet floppy noodle at that point (great, another wannabe female hardass who is anything but, and she's also very pretty... such contrivance)... but I stuck it out and suddenly things got a lot better. She actually DID get far tougher/colder/bitchy in the detached way, and the story got more interesting.
Dramatically, yeah, it did remind me of Person of Interest, somewhere between a procedural and an action-drama, with a pretty even tone (unlike Lost, which had huge dramatic rises and falls). Like Johnny says, I'm not sure if it's "believable" so far, but the actual events seems interesting. Even the fight on the bridge (which I saw coming) seemed pretty ruthless for a regular TV show, and then of course there's a nice little cliffhanger in regards to her hubby.
IOW, I'll give this a shot. Plus, James Spader is just good regardless... although my mental image will always be the young kid with all the hair and smooth features and attitude (although I guess bald is better than the Annette Benning haircut). I recognize his eyes here, and the voice; it's just funny seeing how we all age.