Having worked on this problem before, I know how tough it is to escape the uncanny valley when doing replacement, and these guys have really done impressively well at it (albeit with a fair amount of manual preprocessing and in controlled situations).
http://www.eecs.harvard.edu/~dale/docs/faceReplace_sa2011.mp...
http://www.eecs.harvard.edu/~dale/docs/faceReplace_sa2011.pd...
Having worked on this problem before, I know how tough it is to escape the uncanny valley when doing replacement, and these guys have really done impressively well at it (albeit with a fair amount of manual preprocessing and in controlled situations).