I'm interested to see just how badly this is going to hurt Sprint. A lot of pissed off Sprint customers stay because their phones (not just the iPhone) are locked to Sprint.
Once Sprint can no longer keep people on the network by strongarming their phones how bad is churn going to be? And if people know that they can leave Sprint if they don't like it then how many new customers will Sprint actually retain?
2015 is going to be very interesting to watch. I plan to observe Sprint from the customer base over at T-Mobile next year!
This I think more than anything is what's driving Sprint so hard on Band 26 and 41 as well as pushing hard on triband devices. But their major problem is that most of their customers have only Band 25 devices or devices (like the 5s and 5c) that are only dual band. Hence the push to move new and current customers to new Spark enabled phones.
Frankly, I see unlocking as the one dam in the river that's still preventing the total blowout of Sprint. And I think Sprint knows it.