The author concludes that our friends across the aisle could be in semi-deep doodoo for the next decade. The reasoning is that in 2010 the Dems lost a number of seats they shouldn't be holding, legacy seats held by blue dog Dems in districts that lean right.
Most of the rest were seats in somewhat conservative districts that were gained during the recent Dem wave elections. Greenbaum believes that the upcoming round of census data-driven redistricting/gerrymandering in state houses controlled by the GOP will tend to strengthen Republican control for the next decade.
Given Salon's lean to the left, you know this notion gives them heartburn. We rarely get the opportunity to say to them, "Gosh, I hope they are correct."