Is Philadelphia turning into one big suburb?

The number of jobs in Philadelphia fell to 651,000 last year, "the lowest in Philadelphia's modern history" - yet the Census Bureau says the city's estimated population has reversed half a century of decline and started to rise, up 7,000 last year alone and 30,000 higher than in 2000, notes a new report by the Pew Charitable Trusts' Philadelphia Research Initiative.

What to make of the apparent contradiction? "Simply confusing," says Pew's Larry Eichel. Though he notes there is good news: under Mayor Nutter, crime is actually down. More at Pew's Philadelphia: The State of the City - A 2010 Update" here.

The Philadelphia office market has been stagnant since the 1980s, and factories continue to close. But the number of homes in Center City has surged in the past couple of decades, with new condos and apartments at prices that are affordable by East Coast urban standards.

So I asked Eichel if  the fall in jobs and the rise in population could mean that Philadelphia's fastest-growing neighborhoods - Center City and the riverfront - have become a "bedroom community" for jobs in New Jersey, New York (via Amtrak) and the Main Line.

"It's a reasonable conclusion," Eichel told me. "We just don't have the data yet to know if it's true." The 2010 and the ensuing community surveys should shed light on how commuting patterns have changed, he added.