Once again, there are rumblings that the third - and fourth-largest U.S. wireless carriers may merge to form a larger combined No. 3. But would this be enough to keep the U.S. wireless market competitive for consumers ? Last week Bloomberg reported that Deutsche Telekom AG, the parent company of T-Mobile, is negotiating a possible sale of T-Mobile to Sprint Nextel Corp.. According to The Hill and The Washington Post, some industry analysts believe the U.S. government would approve this merger. Rumors of this merger have been around since 2009, when DT was eyeing a purchase of Sprint. And last weekend, TMOnews reported on an ambiguous non-confirmation/non-denial memo sent to T-Mobile employees by CEO Philip Humm. Given the nature of wireless networks and the current business landscape, T-Mobile probably needs to make some kind of major move if it hopes to survive in some form. In the big picture, it takes a lot of capital to build out high-speed wireless broadband networks that can support an ever-growing number of data-hungry devices such as smartphones and tablets -- especially if streaming mobile video becomes popular, and if the Obama administration is serious about its national wireless initiative to make wireless broadband available to 98 % of the U.S. population. Carriers with the largest customer base -- especially the most customers locked in to pricey two-year