According to this, you can roam onto other carriers at no charge.
No, what that says is that Rogers has signed a (presumably reciprocal) roaming agreement with Bell, Telus, and Videotron. Their agreement with Wind is not reciprocal; it charges Wind wholesale rates and allows Wind customers onto Rogers' network but not vice versa (so you cannot use Wind's subway coverage as a Rogers customer).
Reciprocal roaming agreements have always been possible, but they have to make sense for both parties. I believe MTS/Rogers and Sasktel/Bell have long had reciprocal roaming agreements of some sort because there were benefits for both parties. What's the benefit to Rogers (or Bell or Telus) of a reciprocal roaming agreement with Wind?
That said, there is a potential benefit for both parties in agreements between Wind and Videotron, Eastlink, MTS, and Sasktel. They can offer roaming for their customers and charge each other rates well below the CRTC mandatory wholesale rates.
Wind was unable to do so as an independent company. For whatever reason, they didn't have the ability to come to terms they liked. However, Shaw could change the equation. In Quebec and the maritime provinces, Shaw would likely be better positioned to convince Videotron/Eastlink that they have no interest in expanding into their territory. MTS/Sasktel might be a little trickier, as they compete directly with them for wireline services, but if the terms are enticing enough, they may still be able to work something out.
Maybe, as Shaw rolls out LTE, they might consider re-purposing current equipment in new areas to at least get folks onto the system, and move established areas to LTE.
The existing equipment is still needed to provide HSPA service. Wind cannot simply dismantle the HSPA network immediately as most of their customers will not have AWS-3 compatible LTE phones when that network launches.
I would really like to see the eastern provinces, such as Nova Scotia get Wind coverage, and not just roaming coverage.
I'm fairly confident that Eastlink launching service marked the death knell for any ambitions Wind had in the maritimes. If they expanded there, they would be actively competing with Bell, Rogers, Telus, and Eastlink for a small, low-density population. It would make far, far more sense for them to expand coverage around their existing coverage areas, like Victoria, BC.
WIND only owns AWS-1 spectrum. The spectrum transfers in the second article refer to the former Shaw spectrum.
They also own AWS-3, but I believe only in the Ontario, BC, and Alberta.