By now, the Financial District is used to office building conversions, so what latest FiDi transaction could possibly steal away our attention on the day Renzo Piano's new Whitney Museum is revealed? How about the Nobu Hotel, coming to 50 Broad Street from Robert De Niro and his broker son, Raphael. The horseshoe-shaped building, the Post's Braden Keil reports, will have 140 units and be split up as a hotel/condo. The name obviously comes from De Niro's still shit-hot chain of upscale Japanese restaurants, and the Nobu Hotel will be Japanese themed, offering a new Nobu outpost as well as minibars loaded with sake and complimentary samurai swords for committing hara-kiri (OK, that last one is our idea). This will actually be the second Nobu Hotel when it opens in two to four years, as one will open this summer in Israel. So, does this mean that De Niro's Greenwich Hotel is already old news? Possibly, and we still haven't made it inside the thing!