I am not discouraged by these results. The death of the suburbs, cheered on this website by many, has been greatly exaggerated.
At the same time, I'm starting to see some other trends. Growth in the sunbelt has slowed... and some cities, which have faced decline for decades, are seeing growth again.. notably Newark, NJ and Philadelphia. Philly saw its first population increase since the 1940s during the past decade.
I think what the trends are showing is that people are still leaving the depressed rustbelt areas in droves... but they're not all going to the sunbelt anymore. Of course many are... but some are migrating to other cities within the same region.
Growth in the sunbelt really hasn't slowed all that much. In pure percentage terms, it has - but that is somewhat to be expected, because it's harder to grow as fast in percentage terms from a higher base.
Plus, the US population itself also grew more slowly from 2000-2010 than from 1990-2000. When you control for the lower overall US population growth, 2000-2010 population growth was actually stronger in the South and West than 1990-2000. 84% of the total growth was in those areas this decade vs. 77% in the last. Every state with 2000-2010 double-digit growth was in the south or west, except, arguably, Delaware.