Bits of this have been sneaking around the web for some time, it has now entered: Rumorsville
In an interesting move to improve their 4G coverage, T-Mobile has contacted Clear (fornerly Clearwire) about leasing an amount of their 4G spectrum. This move, should Clear agree to sell/lease the space, puts TMo in a great position to launch 4G much sooner than expected.
Sprint has already committed to using WiMax while its Verizon and AT&T counterparts have chosen the LTE technology moving forward. Tmo had not publicly chosen a route, though it seemed almost certain they would choose the LTE route themselves.
A deal with Clear however, would make jumping on board their existing WiMax connections much cheaper and offer them an instant 4G network with coverage similar to what Sprint can already offer.
An announcement like T-Mo going WiMax should also add more fury to the Sprint/T-Mobile merger rumors as well.
More details should be coming on this soon…