Marshall thinks the industry will change to another way of gauging the relative size of carriers. One measure might be their overall revenue, he said. By that measure, Verizon Wireless appears to beat AT&T once again: For the first quarter of this year, it reported total operating revenue of $19.5 billion, compared with total operating revenue for AT&T's wireless segment of $16.7 billion.
Yet another way to look at size is in terms of spectrum, the licensed frequencies over which mobile traffic flows. By that measure, both of the big carriers lose out to Sprint, which is usually ranked as the third-largest operator.
Sprint only has about 55 million customers, but following its recent acquisition of Clearwire, Sprint has an average of approximately 200MHz of spectrum licenses in the top 100 U.S. markets. By comparison, J.P. Morgan analysts estimated in December that Verizon had an average 105MHz in those markets and AT&T had 89MHz. Leap would give AT&T another 20MHz, still far short of Sprint's total.
Not all spectrum is equally valuable or equally good for each area. But wider spectrum bands can carry more traffic to more subscribers. It's an asset carriers can keep using to accommodate more users or higher data use, Recon's Entner said. "It allows you to be more competitive."