Traffic on smartphones accounted for 45% of ad requests in May 2010, jumping from 22% in May 2008, according to AdMob's latest metrics report.
As of May 2010, the iPhone and Android platforms together accounted for 42% of all ad requests worldwide, driven by strong application usage.
In the past two years, traffic from North America, Asia, Western Europe, Latin America and Oceania all increased by a factor of at least six times.