Been playing this the past few days, and it's absolutely superb. It's the victim of poor marketing and a poor title unfortunately (Spec Ops: The Line just screams low-budget generic shooter to me), and it's been marketed as "yet another" third-person military shooter but it's really nothing of the sort. The storyline is intelligent and compelling, the characters are superb with pretty good AI, and the visuals and level design are up there with Max Payne and Uncharted in terms of attention to detail. The game forces you to make some tough moral decisions and deal with the repercussions that follow; very unusual for a game of this type.
It's held my interest solidly for the past two days, which is something of a rarity for games these days. Highly recommended.