Hooking up with Nokia will help Microsoft overtake Apple's iPhone and Research In Motion's BlackBerry within a few years, according to a new report from research firm IDC.

The combination should boost Windows phones to second place among smartphone platforms worldwide by 2015, IDC said in its latest Mobile Phone Tracker report.

For now, the big story is Google's Android software. IDC expects Android will become the most-used smartphone platform this year, after zooming up to second place in 2010.

"For the vendors who made Android the cornerstone of their smartphone strategies, 2010 was the coming-out party," Ramon Llamas, senior research analyst, said in the release. "This year will see a coronation party as these same vendors broaden and deepen their portfolios to reach more customers, particularly first-time smartphone users."

Overall sales of smartphones will continue growing but not at the same pace as 2010, it predicted. Smartphone sales are expected to grow 49.2 percent this year - to 450 million units - as consumers and business users continue upgrading their devices, it predicts.

Llamas said the Nokia deal will reverse Microsoft's phone slide.

"Up until the launch of Windows Phone 7 last year, Microsoft has steadily lost market share while other operating systems have brought forth new and appealing experiences," he said in the release. "The new alliance brings together Nokia's hardware capabilities and Windows Phone's differentiated platform. We expect the first devices to launch in 2012. By 2015, IDC expects Windows Phone to be number 2 operating system worldwide behind Android."

The chart from the release: