While not technically new, the genre/medium of machinima remains largely unexplored (and underexploited), with a noteable exception of MTV's Video Mods show the channel uses to promote its music.
"The term 'machinima' concerns the rendering of computer-generated imagery with ordinary PCs and the 3D engines of video games (typically first person shooters) in real-time (on the computer of either the creator or the viewer) rather than offline with huge render farms."
The genre has been helped by the release of Electronic Art's "Sims 2" with a a built-in stream capturing feature. It is expected to be futher boosted by the upcoming The Movies game that will put players into a film director's shoes.
An two-year old article by Wired gives a pretty good intro into the genre.
Machinima.com is an info portal on, well, machinima.
There's even a film festival run by Machinima Academy of Art's and Sciences.
Red vs. Blue is one of the more famous machinima series.
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