There is a lot of talk and speculation about Windows Phone as of late. Will it survive or thrive? Was the Nokia the right match? Will the Lumia save the day since it is Microsoft's last chance? All I can say is have patience. This is not a sprint it is a marathon. The rhetoric and criticism was the same for when MS launched Xbox and it took about 5 years before things really started to move in Microsoft's direction.
The comment like "The Lumia 900 is Microsoft's or Nokia's last ditch effort into the US and global market" is crazy. The Lumia 800 and 900 are Nokia's first major phone since the partnership began. Even though Windows Phone has launched 18 months ago it is still in its infancy. What is encouraging is that this is the first phone by Nokia and took 8 months from designed to launch. When Microsoft decides to go into a market it has the cash to take losses for many years and expects to. Will Nokia lose market share during its transition the answer is "yes" but again be patient. If Wall Street slams Nokia then Microsoft can always take Nokia private or even buy them out, so there are options.
The difference between Blackberry and Microsoft is Microsoft is well diversified and has amazing free cash flow and can take 5 years if necessary to start turning things around for its phone business. Each month that goes by Microsoft and Nokia are slowly chipping away at its competition and that's how Microsoft works, death by a thousand cuts. Things are slowly starting to move now and no matter the criticism from the techno blogs they can't stop this momentum.
So be patient my fellow softies we'll get there.