It's shaping up to be a World Trade Center type of morning. The Fulton Street Transit Center has a new completion date, the Port Authority's WTC website has been updated with fresh construction pictures of the 9/11 Memorial and Fumihiko Maki's Tower 4 skyscraper and?most juicy of all?Mayor Bloomberg is assembling all the warring parties for a ground zero summit at Gracie Mansion. About that! Developer Larry Silverstein wants help in financing his WTC Towers 2 and 3, designed by Brit starchitects Norman Foster and Richard Rogers, respectively. The Port Authority wants to build just the lower floors and turn them into retail, finishing the skyscrapers when the demand for Lower Manhattan office space increases, like maybe in 2022 or something. How serious is the Port Authority about the six-story stumps? They've been quietly showing officials renderings of the idea, and now those renderings have popped up in the Post. That's gonna be a lot of I?NY shirts! If the stumps do get built, will this just be another 11 Madison exercise in failed potential?