According to a three month ComScore study ending in January 2012, U.S. smartphone market share  is really turning out to be a two pony race.

Google and Apple were the only platforms to increase market share with 2.3% and 1.4% gains respectively.  Research in Motion and Microsoft were the biggest losers shedding 2% and 1%.

Almost half of all smartphones are now powered by Google’s Android operating system which sits at 48.6% U.S. share.  Apple’s iOS sits at a respectable 29.5% share.

Research in Motion’s BlackBerry is now down to 15.2% and falling with no new hardware of consequence that could turn things around for the company until late this year at the earliest.  To make matters worse RIM will have to contend with the iPhone 5 which will ship before the first BlackBerry 10 device.

I don’t believe there is much doubt that RIM’s U.S. smartphone share will hit single digit percentages before BlackBerry 10 comes out.  The question, however, is if RIM will be able to stay in front of Microsoft who, although is loosing market share, is losing it more slowly than RIM.