Those customers will still get unlimited data, they just might not get it as fast as they were expecting. The overwhelming majority of customers won't ever run into this restriction, it seems -- as other carriers have already done, it looks like Sprint will be constraining the few to save the experience of the many. "Our goal with [the quality of service practice] is to prevent some portion of that three percent going forward from negatively impacting the other 97 percent of customers," Hall writes.

While that's not an unreasonable viewpoint to have, it still isn't exactly "unlimited" data if you're going to have your speed constrained. To that end, it looks like Sprint will be writing this into its customer agreements going forward. These new restrictions will only apply to people who new customers who purchase an unlimited data plan starting today, or current customers who upgrade their handsets and remain on unlimited data going forward.