In case you don't want to read their (somewhat pretentious) introductory
material, in a nutshell, they focus on US politics (ie. they are mainly
concerned about what bias articles have on a scale ranging from radical
left to radical right), and are trying to create a wiki where different
viewpoints can coexist so editors have no reason to fight edit wars (like
Wikinfo tried in ages past, except they want to take a more software-driven
approach). They want to break up articles into separate parts depending on
how bias-prone they are (pure facts, context, opinions) and use editors'
self-assessment of political POV to show them the page revision just after
the last edit from someone with the same POV.