Got this from some relatives this morning (via mail) and been trying it, even suggested it to some other relatives by the afternoon.
It's a pretty good game...I can't say I am all that impressed with the AI as some reviewers are, nor am I impressed with the graphics...but there's something rather likeable, enough to keep me playing for hours straight.
It's dang hard though, and it has no save function that I know of, only checkpoints. Rather frustrating, but still, there's something rather captivating about it, can't put my finger on it. I know it's been out a while elsewhere, but I wasn't too keen on it when it came out, and probably wouldn't have tried it if I hadn't gotten a free copy.
Now I think it's one of the best FPS games out this year...thus far at least.