September 2012 comScore: It's a slow death for RIM.

As far as market share goes, comScore shows that Apple and Google are still growing, Microsoft is flat, and RIM just might end up behind Microsoft before BB10 comes out in January.  While Microsoft's market share was flat, it (ever so slightly) increased its total number of subscribers as the total US smartphone market grew by about 2.5M; RIM hasn't stopped shrinking in total subscribers, though.

Top Smartphone Platforms 3 Month Avg. Ending Aug. 2012 vs. 3 Month Avg. Ending May 2012 Total U.S. Smartphone Subscribers Ages 13+ Source: comScore MobiLens
	Share (%) of Smartphone Subscribers
	May-12	Aug-12	Point Change
Total Smartphone Subscribers	100.0%	100.0%	N/A
Google	50.9%	52.6%	1.7
Apple	31.9%	34.3%	2.4
RIM	11.4%	8.3%	-3.1
Microsoft	4.0%	3.6%	-0.4

Over the trailing 12 months, Apple and Google continue to grow at the expense of mostly RIM.

Looking at a 3-month rolling average of month to month change in market share (percentage point difference), it's a lot clearer what's going on.

• Google is still growing, but it is no longer growing at an eye-popping rate;
• Apple has been very slowly gaining momentum;
• Microsoft is mostly treading water;
• RIM is the near-opposite reflection of Google -- continuing to lose market share.