The world has changed
With these little computers, called smartphones, people learned that the platform is not locked anymore. RIM had bad time, as they wanted t.o lock everyone in. The iPhone and various Android phones demonstrated that interoperability is key for the mobile devices. At some point you replace an less inoperable device with another, no matter what - and this is especially true for professional work. So, there is not much recommending power to die hard Windows IT staff. They may be locked in with Microsoft, but the mobile users aren't anymore - and this will be great challenge for Microsoft.
By the way, all the pros you listed are because of Nokia and all the cons, because of Microsoft...
