I think our games vocabulary is a bit impoverished. When most people think of games they think of fictional, often fantastic stories. Killing elves, post apocalyptic settings, shooting up all sorts of big bads. But games can also offer interesting ways to engage with the real world. To borrow a word from print I think that non-fiction can provide a compelling way to describe games that create playable environments out of real world data, documents and statistics.
There are other approaches for describing game genres. Terms like educational games, games for change, and serious games try to define genre of games by the intended user experience. Each is a description of the goal of the games, not their content. In my experience this is not the way we describe other media, at least other successful generals of media. Do you want to watch a educational film? Are you interested in reading an exciting new educational book? The idea of serious games is equally problematic. If a military simulation like Americas Army is a serious game are we suggesting that engaging games like Fallout 3 or Bioshock are frivolous?
I think there is a much broader, largely unexplored category for games.
I think we are getting to a point where dividing games into fiction and non-fiction makes sense. Gamers are getting older and there is good reason to believe that as they do they will be looking for other ways to engage with games. If we think about the experiences of watching a documentary, or reading a great work of non-fiction, we can get a taste of what these games could be like. Take those appeals to facts, to real data, and make playable experiences. Below I have three examples of different kinds of games that fit within this genre. Each of these create playable experiences out of real world data.
Science Games:

Example Operation Resilient Planet
In Operation Resilient Planet you recreate the field work of contemporary underwater ecologists. Through a series of mini games built around these scientists’ actual work, players gather data which they then deploy in arguments with other scientists. In practice it is a bit like Phoenix Wright meets a great episode of Nova. The game is built for middle school students, but I found it to be quite engaging. The same basic idea, using real scientific data to make a engaging game space, is in action in the discovery channel’s Sharkrunners game.
Historical Games:

Example Colonial Williamsburg Revolution
Grounded in the historical expertise of folks at Colonial Williamsburg this multi-player Neverwitner Nights mod lets people play through the events around the American Revolution. There are a lot of other examples of games that model a variety of different historical ideas. Commercial games like Civilization, military games like Rome Total War, and the Romance of the Three Kingdom’s series. There are still a lot of less explored ways to build historical games. Things like biographical games, and non-military period piece games are still largely unexplored.
Political Games:

Ayiti: The Cost of Life
Try managing the health, education and finances of a family in Haiti. Don’t let the cartoon-y look of this one fool you, its pretty grim. There are a ton of other examples of these sort of political games, and some lively discussion of these sorts of games as journalism or as games for change. For some other neat examples of these sorts of games see Peacemaker, a Civ style middle east simulator, or the game of non-violent resistance, A Force More Powerful.
Conclusions:
To abstract a little bit from these specific examples, the game play in each of these games hinges on real world experience; scientific data, historical documents, economic information, and develops a playable space from those experiences. History, science and politics were the first three sub-genera that came to me. What other sub-categories of non-fiction games should we be thinking about? Or am I just completely wrong headed about this?