Eager to get its LTE ducks in a row, T-Mobile announced today that it plans to begin trials of the next-gen network this summer. But here's the kicker: despite being tardy to the high-speed party, it plans on deploying true 4G in 2013, throttling ahead to the latest and greatest version known as 3GPP Release 10 -- also known as LTE-Advanced. Hitting this mark is crucial for T-Mobile, primarily because Sprin