AdMob has released its latest metrics report, revealing impressive global growth of the iPhone, as well as the immediate impact of new Android devices in its November 2009 AdMob Mobile Metrics Report.

The report also highlights that one of the major trends in 2009 has been the growing share of requests from smartphones and increasing usage of Wi-Fi.

According to the report, smartphones accounted for 48 percent of mobile Web and application requests in the United States in November. That’s up from 31 percent in November 2008. Wi-Fi usage has also taken off, with 24 percent of requests in the United States coming in over a Wi-Fi network in November compared to 8 percent in November 2008.

The report also examines growth in unique iPhone and iPod touch users since January 2009, finding more rapid growth outside of the U.S. In November 2009, 50 percent of unique users were located outside of the U.S., an increase from 39 percent in January 2009. Of its top markets, Apple devices experienced the strongest percentage growth in Japan, France and Australia in 2009.

AdMob, which is in the process of being acquired by Google, reports that Android devices have made their presence felt as well. In the second half of 2009, Android growth has accelerated in accordance with the release of a number of new handsets that run the open OS. Six months ago, a single Android device, the HTC Dream (G1), generated 92 percent of Android traffic, while in November 2009 the same device accounted for only 37 percent of requests. The Motorola Droid, HTC Magic and HTC Hero generated 22 percent, 21 percent and 9 percent of Android requests worldwide in November 2009, respectively.

Additionally, the report found that the top five U.S. devices based on Wi-Fi requests generated were the iPod touch, iPhone, Sony PSP, HTC Dream (G1) and Motorola Droid. Fully 36 percent of iPhone traffic in the U.S. was over Wi-Fi, considerably higher than other Wi-Fi capable devices. Less than 10 percent of traffic from the major Android devices came over Wi-Fi.

The iPhone accounted for 71 percent and the iPod touch accounted for 29 percent of total unique users from Apple devices. Android generated 27 percent of the requests from smartphones in the U.S. in November 2009, up from 20 percent in October 2009. Eighty-eight percent of requests from Android devices came from the U.S. in November 2009.