Donovan joins Sprint, T-Mobile in Gig LTE race. This will increase capacity 4-5 times, so much that I'm predicting wireless is about to enter an age of abundance. "Unlimited" plans with speeds over 100 megabits and caps well over 100 gigabytes/month will make sense at consumer prices. As T incorporates 5G in the next few years, especially Massive MIMO, costs will go down even further.
AT&T announced plans to increase capacity 5X, with 4 carrier aggregation, 4x4 MIMO and 256 QAM - the blessed trio of the Gigabit Internet. See For non-engineers. How LTE gets to the gigabit: 4x4 MIMO, 4 Band Carrier Aggregation, 256 QAM for my attempt to explain this to ordinary people. The gig is shared across the cell site, but individual users will usually get hundreds of megabits unless at the edge of the cell or behind walls. Deployment in 2017 will probably be modest because most of AT&T's cells rarely see congestion today.
Gigabit LTE technology is so cheap that AT&T can do this without raising capital spending. Verizon & Vodafone estimate that wireless costs are going down 40% per year.