"Although there appears to be some stability in the Midtown market, it is still too early to definitively say that vacancy has peaked," James Delmonte, VP and director of research for JLL's New York office, says in a release. "While it is important that activity has returned to the market, it is not likely that it will lead to substantial absorption of space over the next 12 months. Much of the current deal flow in the market consists of renewals and relocations, neither of which will reduce current supply levels."

The fall 2009 Skyline Review says that Manhattan's top-tier office buildings saw overall average asking rental rates drop 17.8% in the past six months, compared to a decrease of 18.7% between fall 2008 and this past spring. In terms of dollars, that translates into an average $68.73 per square foot, compared to $83.66 per square foot six months earlier.

For Midtown trophies, average asking rental rates dropped by 17.2% from six months earlier, falling from $88.88 to $73.58 per square foot. Last spring, the Skyline Review had noted a 24.3% drop in rents for Midtown trophy buildings.