CoStar Group Inc. recently released its list of the top 50 biggest commercial lease deals by size in the New York metro area for the first two quarters of 2011. The list revealed that the Top 5 deals finalized in the first six months total an astonishing 4.3 million square feet. This trumps the meager 1.7 million square feet that was leased by the Top 5 deals during the same period last year.

Some of the major agreements included Comcast/NBC Universal's renewal of its lease at 30 Rockefeller Plaza, Condé Nast's 1 million square-foot lease at 1 World Trade Center Plaza, and Li and Fung's 482,000 square-foot lease at the Empire State Building.

The major lease deals have also affected commercial rent prices. Cushman and Wakefield Inc. reports that 2011 has seen a 2.2 percent increase in the average asking rents so far this year. Landlords are averaging $55.52 per square foot through the first two quarters.

Average vacancy rates for Manhattan are also down from 10.8 percent at the mid-year point in 2010 to the current rate of 9.4 percent.