Oles Shishkovstov, CTO of 4A Games was interviewed by eurogamer. He talks about the technology behind Metro 2033 and mentions using FaceFX.
http://www.eurogamer.net/articles/digitalfoundry-tech-interview-metro-2…
It's a good read about what is sure to be one of the best games in 2010. Congrats to 4A Games.