BlackBerry's market share has been highly debated over the last couple of years, and with the recent news about being acquired, most would think it would be taking a hard hit in this aspect.
According to comScore's latest report, BlackBerry's market share in the U.S. has dipped in the three months dating from May to August 2013 from 4.8% to 4.0%. The unfortunate streak of BlackBerry losing market share in the U.S. continues this quarter as well (BlackBerry's U.S. market share was at 5.4% in Feb 13, and 7.2% in Nov 12).
The good news for BlackBerry is Microsoft's Windows Phone OS has really taken off in the U.S. either, as they only increased from 3.0% to 3.2% market share in the same time period. Microsoft's WP market share has stayed around the 3% market for the last 4 quarters as well, being unable to climb out of that plateau for a while.
As mentioned before, these numbers reflect market share up til August. The news about BlackBerry possibly going up for sale, and later getting a bid from Fairfax, didn't happen until mid-September. Odds are the next comScore report (from September - November 2013) will give us a better idea of the type of drop off BlackBerry may be seeing in the future due to the news.
Also, comScore doesn't differentiate between BlackBerry's legacy OS, and BlackBerry 10, so the 4.0% is not BlackBerry 10's market share, but BlackBerry as a whole. As a result, this report can't really be used to determine any BB10 traction in the U.S.