The Dolphins had supposedly considered re-signing Brown after DeAngelo Williams—perhaps Miami's top free-agent target at one point—was re-signed by the Carolina Panthers to a five-year, $43 million contract. But a trade that sent Bush to Miami and will net the New Orleans Saints safety Jonathon Amaya effectively ushered Brown off the Dolphins' radar.
So who pursues Brown now?
Rotoworld seems to think that the Indianapolis Colts and Tampa Bay Buccaneers are good fits for Brown, but the Colts are pressed against the salary cap with Peyton Manning's pending long-term deal and intent on re-signing their own free agent running back Joseph Addai should the salary space allow, and there aren't any concrete reports tying Brown to the Bucs—just pure speculation.
Baltimore Ravens fansite Ravens 24x7 suggests that Brown might be brought to the Baltimore Ravens to back up Ray Rice and provide the Ravens with a potent one-two punch with Willis McGahee on his way out.
Expect more suitors to join the Brown auction soon. Next to Ahmad Bradshaw and Cedric Benson, Brown is likely the most talented running back currently up for grabs on the open market.