Nokia is unlikely to sell phones running Windows Phone 7 software because Nokia "in their fashion," is "just as insistent on control over their ecosystem as Apple is," writes soon to be ex-Nokia employee Watts Martin on his blog.
Previously there were rumors that the two companies could hook up on some sort of smartphone project.
Here is Watts' argument for why Nokia is as controlling as Apple:
Symbian and MeeGo are both open source, but Nokia is by far the most important corporate developer of both (let’s face it, Symbian never really had anyone else working on it). The API for both of them is Qt, developed by Nokia-owned Trolltech. Nokia’s mapping and navigation is supplied by Nokia-owned Navteq. Their search tools are being developed with pieces (and people) they kept from MetaCarta. They don’t have a closed “app ecosystem” like Apple, but if you are supplying software components in Nokia’s ecosystem that they come to rely on, it’s a good bet they’re going to buy you or write a homegrown replacement for what you do.
For these reasons, it would be out of character for Nokia to just decide to give up control to Microsoft.
Further, Watts says Windows Phone 7 is weaker than MeeGo. It doesn't have multitasking, it has fewer apps, and it has less enterprise support.
Overall, Watts' thinks Nokia's OS strategy is good. The biggest problem for the company is user experience and its irrelevance in North America. And it's not like Microsoft would help with the latter of those two.