Update: A Valve representative responded to Gamasutra's request for clarification on revenue splits by highlighting the Skyrim Steam Workshop page, which notes that all revenue from sales of Skyrim Steam Workshop content will be split between Valve, Bethesda and the content creator(s).
This opens up more avenues for budding and established game developers to get paid for their work - as former SimCity artist Bryan Shannon is by creating Cities: Skylines mods - and furthers Valve's long-stated aims of democratizing content creation for games on its platform.
