But there's more encouraging news coming from Western Europe. There, Microsoft's Windows Phone 7 has been far more successful. From Q3 to Q4 of 2010, Microsoft's mobile OS market share grew 100%, doubling their presence. Also, Microsoft's presence grew 18% year-over-year. Even when accounting for the 3.2% increase in the Western European mobile phone market, WP7 still showed a strong introduction.
Adding to the significance of their success is the fact that WP7 wasn't released in many languages. If it had been released with more localized languages, they may have grown even further. Of course, Android and iOS still won out in Europe in 2010, as they did in the U.S.
source: IDC via WMPoweruser