Inward Trend in Building Permits?

The EPA just released results of a study of residential construction trends to see if there is a real shift inward, or if most construction is still on the suburban fringe:

...In more than half of the largest metropolitan areas, urban core communities have dramatically increased their share of new residential building permits.
* The central city has more than doubled its share in 15 regions (of 50 studied).
* The increase has been particularly dramatic over the past 5 years.
* Data from 2007 show the trend continuing in the wake of the real estate market downturn.

However, in many regions, a large share of new residential construction still takes place on previously undeveloped land on the urban fringe...