A report released last week by Comscore finds that for the three months ending May 2010, RIM led among smartphone platforms with 41.7 percent market share. Apple ranked second with 24.4 percent share, followed by Microsoft (13.2 percent share), Google Android (13 percent share) and Palm (4.8 percent share).

The biggest gainer among Smartphone platorms over the previous three months according to the research firm was the Android platform which increased its share from 9% to 13%. The data should be treated with suspicion, however, as Comscore admits the May data does not include the impact of Apple’s launch of iPhone 4.

The company did not release the methodology for the study so its unclear how the data was collected, what if any sample size was used etc.

Among all mobile phones, Samsung was the top handset manufacturer in the U.S. mobile phone industry with a 22.4 percent market share, LG ranked second with 21.5 percent share, followed by Motorola (21.2 percent share), RIM (8.7 percent share, up 0.5 percentage point) and Nokia (8.1 percent share).