Sprint has just announced that they will be rolling out 4G LTE aggressively over their 1900MHz spectrum. I know people were hoping they'd shut down the iDEN network by now to make way for a new 4G network on that 800MHz spectrum but they won't complete the shutdown until mid-2013 when they've been able to migrate all their customers. We were hoping they'd launch LTE on their 800MHz spectrum but they note that they will work to get it up and going there after the iDEN migration is complete.
The good news is that Sprint's already working on this and are working to get things going in mid-2012. And when do they expect it all to end? Mid-2013.
Android Phone, Sprint to Aggressively Rollout LTE Over 1900MHz Spectrum Starting Mid-2012 Along With Capable Devices, Network Largely Complete by 2013