The Future Belongs to … Windows Phone 7?

The flip phone better say its last prayers.

According to research firm IDC, smartphone growth is exploding in 2011. The firm’s latest Worldwide Quarterly Mobile Phone Tracker report reveals that vendors will ship a total of 472 million smartphones in 2011 compared to 305 million units shipped in 2010, a year-over-year growth of 55 percent. That figure will nearly double to 982 million by 2015.

IDC is also sticking to its guns that Windows Phone 7 is going to outgrow all other smartphone OS’s in the next four years, even as it forecasts that Microsoft’s mobile OS will actually dip in the current year, from 5.5 percent worldwide market share to a dismal 3.8 percent.

But by the year 2015 the sun will be shining on Windows Phones, according to the IDC smartphone report, and Microsoft’s struggling OS will have a 20.3 percent worldwide mobile market share and be second only to Google’s Android OS.

Worldwide Smartphone Operating System 2011 and 2015 Market Share and 2011-2015 Compound Annual Growth Rate

SOURCE: IDC

These projections are similar to IDC’s late-March smartphone forecast, with Windows Phone 2015 market share forecast dipping ever-so-slightly this time around, from 20.7 percent in March to 20.3 percent now.

Such a prophecy is jarring for many because nothing in the present indicates that Windows Phone 7 is a winner. Consumer enthusiasm about the platform is low and its global market share will likely drop below 5 percent this year. If a comeback is in the cards, it won’t start until next year at the earliest. Windows Phone’s next version — called “Mango” — has a slew of new features, but it will not be available until sometime this fall.

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And then there’s Nokia. IDC views Microsoft’s partnership with Nokia as an ace in the hole where Nokia’s global muscle will prop up Windows Phone 7 in areas outside the U.S.

An excerpt from IDC’s report:

“Windows Phone 7 will benefit from Nokia’s support, scope, and breadth in markets where Nokia has historically had a strong presence. Until Nokia begins introducing Windows Phone-powered smartphones in large volumes in 2012, Windows Phone 7/Windows Mobile will only capture a small share of the market as the release of Mango-powered smartphones are not expected to reach the market until late 2011. Nevertheless, assuming that Nokia’s transition to Windows Phone goes smoothly, the OS is expected to defend a number 2 rank and more than 20% share in 2015.”

Shane O’Neill covers Microsoft, Windows, Operating Systems, Productivity Apps and Online Services for CIO.com. Follow Shane on Twitter @smoneill. Follow everything from CIO.com on Twitter @CIOonline and on Facebook. Email Shane at soneill@cio.com