Asked if the positive trend will continue, he says, "Our visitor attraction is through the roof, and that has sparked business development. Center City is still one of the best bargains in the Northeast. We're cheaper than Boston, Washington and New York, and offer a great, vibrant city. Historically, we've never seen much relocation from New York City, but Select Greater Philadelphia [a local nonprofit] is working to correct that."

Two additional first-quarter reports support Derham's view. The local office of Jones Lang LaSalle also points to Comcast's expansion, which does not stand alone. The report notes that a new law firm lease joined renewals to take Seven Penn Center's occupancy to 90%, and BDP expanded to 80,000 sf at Penn Mutual Tower, as GlobeSt.com previously reported.

In assessing the entire region's office market, Colliers Lanard & Axilbund says the Center City and suburban submarkets are "in a much healthier position than two years ago." Submarket office vacancies of between 15% and 20% were common in early 2005, the report says. In early 2007, "most submarkets have dropped to the 12% to 13% range. We anticipate further decreases in vacancy over the next six months with encouraging job growth projections," it concludes.