How about a news site that actually helps reporters/ photographers/ editors collaborate to create news, instead of just aggregating/ ranking already written articles?
The basic blocks of the news stories is source material: photos, quotes, observations that can be submitted by anyone.
Every contributor (sources submitting photos/ quotes/ etc, writers, editors) and every component (the photos, the source material, the finished article) are rated, and feedback goes both ways.
So, the best sources/ writers/ editors eventually float to the top: