The newest Nielsen Ratings marketing research report is out and it details the continued rise of the Android OS. According to the report, Android has increased its OS marketshare in the United States from 39% in the second quarter to 42% in Q3. This expansion is largely at the expense of both the Windows Phone 7 OS and RIM. The Blackberry OS dropped down to 18% from 20%, and Microsoft's mobile OS slid from 9% to 7%. Apple's iOS remained flat at 28% in both quarters.

Source: BGR and Nielsen