Well, seeing that Insurgency: Sandstorm was on a sale, I just picked it up for him (and myself). Seems to have a lot in the map making scene, and that's a really important factor for him.
It also helps that the prior Insurgency game has the most hours on his profile, by far. Gave me a good hint that he should enjoy this one.
Thanks so much!
EDIT: My dad just got back to me, and loves the gift. Apparently that's where most of his online buddies went and still are. Nailed it!
I liked it just fine!
I know there are a lot of Asimov diehards that found it disappointing. I don't know why. The iRobot book wasn't even really a book, it was a collection of short stories. Not exactly an easy thing to adapt to a movie.