I tend to call someone out when they make wild claims that may generate unsubstantiated rumors, and unfortunately some ppl seem to have a natural tendency to repeatedly do that.

Anyways, to address the possibility of running Windows on N900 to gain access to its large software library:

Having Microsoft make a port of Windows to Nokia N900 is as likely as Apple making a port of iPhone OS (iOS) for the Palm Pre. It has a very very low probability of happening due to many reasons. (of no strategic value, low financial return, inconsistent with past corporate behaviors, legal spaghetti, low gain for the amount of effort, etc)

Even if that happens, the performance will be super shite due to the whole stack being targeted for a platform that is so much higher in performance to render it unusable for the application discussed in this thread.