It's official. Sprint Nextel is now simply Sprint Corporation, as SoftBank completes its high-profile buyout of the wireless provider. Japan's third-largest carrier now owns a controlling stake in the United States' third-largest carrier. Fitting, isn't it? The deal, which has been in negotiations since last fall, is worth some $21.6 billion. $5 billion of it is being used as a cash infusion to take on future projects, and the other $16.6 billion is going to Sprint shareholders. And Nextel? It's gone for good… Reuters reports: "Analysts expect Japan's SoftBank, an aggressive competitor in its home market, to make big changes at Sprint once its takeover of the U.S. mobile service provider closes on Wednesday. They say Sprint needs an overhaul after years of customer losses that have hurt its bottom line.