Om likes to call it Sextel, and owning a national footprint in the 2.5 GHz band might be sexy for investors: Om Malik writes about the MMDS band (2.5 GHz), which is largely owned by Sprint and Nextel. He and others he links to (and his first commenter) all believe that a merger would turn MMDS idle and then force WiMax into 5.8 GHz in the U.S. WiMax's first flavors will operate likely in 5.8 GHz, 3.5 GHz, and 2.5 GHz. But 3.5 GHz is available primarily in Europe right now as their preferred licensed band.
But remember that there's a proposal by the FCC on the table to carve up MMDS into different pieces while retaining its limited current function for educational broadcasting. This new carving would make it appropriate for 3G cellular services up to 5 MHz wide (3x flavors of 1xEVDV or 1xEVDO).
Because the FCC also created a plan to migrate Nextel's messy chopped-up set of frequencies into a continuous block elsewhere and allow them to pay for public-safety system upgrades to use their old spectrum, it's barely possible that the FCC will require Nextel and Sprint to accept their revised MMDS proposal as a condition of the merger. Powell has been liberal on allowing media mergers but conservative on spectrum utility, focusing on maximizing potential users and licensees (or unlicensees).
The revised MMDS plan would open up space because existing license holders wouldn't have as much spectrum in the new plan, but it would be more highly optimized for useful services, which could include WiMax.