ROBERT X. CRINGELY on spectrum auctions. “Why are all these companies so excited? Because the 60 MHz of spectrum that’s about to be auctioned is the last prime real estate for mobile communications that will be available in the U.S. for decades to come. . . . Some pundits (that would be me) think Google will bid to win its spectrum block, then will trade that block to Sprint/Nextel for some of that company’s 2.5-GHz WiMAX licenses that are far better suited for data.”