My favorite part of the whole Windows Phone experience is how efficiently updates are pushed out, and how that obviously keeps fragmentation to a minimum. Unfortunately, Microsoft is taking a slight step in the opposite direction with the next WP7 release, codenamed Tango. As the leaked roadmap above shows, Tango is going to focus on "products with the best prices."
In other words, cheap smartphones.
Tango will be rolled out to devices that should be more accessible to people. If I had to take a guess, I would say that those devices will be under $50. Then again, "accessible smartphone" can mean numerous price points. We'll just have to wait for Q2 of 2012 to see what actually pops up in stores.
More importantly than Tango, however, is "Apollo." It will be the next-generation Windows Phone platform, so think of it as Windows Phone 8. Those devices (and the operating system itself) will roll out in Q4 of 2012; it makes sense, considering the iPhone 5 should be released sometime in the fall, as well.
Given the success of WP7 already, I expect for Microsoft to pump even more resources and time into Tango and Apollo to make the platform even better. 2012 may be Microsoft's golden year to get back into the smartphone race.