We knew more or less that an announcement of this sort was coming. Back in July, Dan Hesse had teased us face-to-face with the promise of a "great story this fall around 4G," and now the time to tell that tale has arrived. At its strategy event today, Sprint finally went public with plans to "simplify its network" by converting its CDMA 1900MHz holdings and LightSquared's 1600MHZ spectrum ("pending FCC approval) to LTE, an i