http://news.ycombinator.com/item?id=2402027
politics? I don't think so. Economic inequality is a very interesting social phenomenon, though it is often written about in a heated/political way.
If readers are willing to tag stories not just as "good" or "bad" but with categorical labels, then suddenly the news aggregator "knows" a lot more about the data its serving up. You could have categories at the top, preferential sorting for users, and more.