"This will be the new crown jewel of the skyline," said WTC developer Larry Silverstein during a press conference announcing the commission. Foster and his team are beginning the design and the building is expected to be completed in 2011. Foster's other works include the soon-to-be-completed Hearst Tower here and the Boston Museum of Fine Arts.

New York State Governor George Pataki said Silverstein and the Port Authority of New York and New Jersey have a 90-day deadline to "resolve differences on every element" regarding the rebuilding effort. "We're going to keep every option open."

"We're going to come up with a resolution," said Silverstein, adding that he expects his firm will develop the entire site. He notes that buildings on the site are ideally suited for use by corporate users requiring large amounts of space, as opposed to residential use. "That's its best and highest use."