If I've been a bit quiet, I've fallen into DEUS EX: HUMAN REVOLUTION.
I think this may be the best video game I've ever played.
It's a game you can play like Call of Duty, and kill everything that comes against you. Or, you can play stealth, and not kill anyone (which is how I try to play it). There are multiple ways to play each mission. Some of them involve social engineering.
A while ago I blogged about "conversational combat." (Posts are here and here.) Too many games treat dialog as exposition, but not gameplay. Just keep clicking on the NPC, and he'll tell you everything you need to know.
In DX:HR, there's quite a bit of information that you only get if you say the right things -- browbeating some characters, placating others. You can even upgrade your character so he's better at saying the right things.