Video games have made many technical leaps over the years, but facial expressions remain a largely unexplored frontier. This is unfortunate, as facial expressions are one of the best ways to communicate emotion.
In Neil Stephenson's Snow Crash ordinary people have access to virtual-reality version of the Internet, accessible even from phone-booth like headsets in gas stations and malls. Users have the ability to choose their own avatar, a fully three-dimensional character that can be anything at all as long as it is roughly the size of a human being. Stephenson, tongue firmly in cheek, pokes fun at Internet culture by describing how many users will create gigantic walking dongs to represent themselves. But Stephenson also portrays a sort of class system among users which is based on the realism obtained in an avatar, with a heavy emphasis on facial expressions. The ability to accurately portray facial expressions gave an avatar an uncanny realism and showed that the user was either technically gifted or wealthy enough to hire those who were.
Snow Crash may be an adventure through an America that only the most cynical could call plausible, but the insights into the importance of expressions on virtual characters were ahead of its time. Facial animation is one of the most important fields in gaming today, but also one which is often only appreciated by those who are already inclined to notice.
While games have constantly made stabs towards artistry, success in that realm remains elusive. One of the largest obstacles is tricking the player into caring about a character which is known to be entirely virtual. It is too easy to ignore the pains of virtual characters that lack any human element, and recent sandbox games illustrate that point. Remorse is not something commonly felt while running over crowds of innocents in Grand Theft Auto 4, but this is not surprising. The people roaming the streets may run, or scream, or (most likely) shout obscenities, but they are still nothing more than algorithms, reacting mathematically to all situations. Their faces are largely blank, and could just as well be covered by virtual paper bags.
GTA 4 is only one example of many. Another example would be the game Bioshock, a game trying hard to present itself as a shooter with some serious things to say. Bioshock's most memorable scene (SPOLIER ALERT) is the confrontation with Andrew Ryan, the villain who is central to the game's obligatory Big Plot Twist. But even in that vital scene, Andrew appears as no more than a mannequin. His facial expression is limited to smug and scornful as the player gradually murders him with a golf club, and while some of that might be attributed to Andrew Ryan's insanity, it is still difficult to swallow his mechanical response to the blows which he knows are coming. This is a barrier to feeling the full impact of a scene which is otherwise beautifully written and scripted.