Sprint PCS Wi-Fi Access's bilateral roaming agreement with Truckstop.net clarifies the plan: Sprint's services builds out the locations, and the Wi-Fi service roams: This is the second bilateral roaming agreement that Sprint PCS Wi-Fi Access has announced, and Truckstop.net will have a large footprint. Who is building the footprint? Sprint. When Sprint said last year they would roll out 1,300 of their own locations, it might have been closer to say they would be building locations for others and as part of those deals have roaming access.
Sprint PCS Wi-Fi network originally comprised just Wayport locations. The additional 1,300-odd hotspots could be their recent deal with STSN (about 700+, with 900 under contract to build) and Truckstop.net. Truckstop.net has 3,000 locations that Sprint is contracted to build out with Wi-FI.
They may yet surprise us with their own deals, but this set of information puts the whole plan into clear focus.