Microsoft, Facebook, Research in Motion, Avaya, Qualcomm, Yahoo, Oracle, and Brocade have all signed a letter to the Federal Communications Commission (FCC) in support of the proposed AT&T and T-Mobile merger.

The Microsoft-led letter, first reported by New York Times, argues that the merger is necessary to support America's voracious appetite for wireless broadband—and keep America competitive on a global level. Of course the unspoken implication is that currently, carriers can't keep up up with the affected parties' Web-intense applications.

"Many policy related efforts will not be able to quickly address near term capacity needs. The FCC must seriously weigh the benefits of this merger and approve it," the letter says.

"An increasingly robust and efficient wireless network is part of a virtuous innovation cycle and a healthy wireless ecosystem is an important part of our global competitiveness."

The letter also posits that it's a good thing AT&T has "indicated" it will migrate T-Mobile's network to LTE, thus expanding LTE access to 97.3 percent of the U.S. population.

"AT&T has stated that its LTE deployment will bring significant benefits to residents of rural areas and smaller communities, where the benefits of real-time video and similar capabilities are most urgently needed to fill gaps in physical infrastructure for healthcare, education, and other social needs," the letter says.

In a statement, AT&T chairman and CEO Randall Stephenson said, "we're pleased to have such strong support from Silicon Valley for our merger. These are among the most innovative companies and investors in America, and they recognize the link between our merger with T-Mobile and continued innovation in mobile broadband."

Last week Sprint filed a formal petition going against the proposed merger, asserting that AT&T is already the "largest holder of unused spectrum" and does not need the merger to massively improve its network.

AT&T first announced plans to acquire T-Mobile for $39 billion in March arguing that the purchase would help stop the spectrum crunch and spur the companies' deployment of 4G service to a greater population. In April, the FCC formally kicked off its investigation of the deal by opening a public notice, followed by a Senate Judiciary Committee hearing in May.

Ever since, Sprint CEO Dan Hesse has been vociferous in his opposition to the merger and has attracted support from an odd mix of consumer groups. He argues that the merger would destroy competition by creating a duopoly, raise subscription prices, weaken service, etc.

Meanwhile, check out the latest results from PCMag roadies as they drive cross-country to compare the broadband speeds of six carriers, in this year's Fastest Mobile Networks feature.

Editor's Note: This story was updated at 1:50pm Eastern with comment from AT&T.