His raise makes no sense to me. He had a fairly good hand. If you indeed were on unimproved big aces, he can just call and win a good-sized pot. If you had AQ or KQ, and he knows you aren't really weak, his silly river raise will not get you to fold. Basically, I think he made the worst move in poker -- betting the river with a medium strength hand. Better hands will not fold, and worse hands you are beating anyway making the bet more risk for no reward.

This being said, his raise on the river looked a lot stronger to me, because I wouldn't expect a raise from such a mediocre holding. I still would've called but I'd feel like I got trapped by a set or strange two pair. Your read on this guy was aggro -- any further detail? Stupid aggro? I'm just getting back into shorthanded play, so these situations are interesting to me.