The September 2009 Mobile Metrics Report from AdMob was released today and it provides some interesting insights into the growth of the mobile web.

The firm, which serves up ads to mobile devices from over 15,000 mobile sites, said that it served up more than 10.2 billion advertisments in September 2009, double the number it served up in September 2008.

In fact, the total was more than six times greater than September 2007 when the company first started publishing its numbers.

Although the numbers may not be necessarily representative of the mobile Web as a whole, because it is pulled across ads served on more than 15,000 sites and applications, it is instructive in gauging the growth of the mobile web around the world.

The country with the most adMob requests was the U.S. with 4.8 billion pages served up followed by India (668 million) and Indonesia (485 million. Canada was seventh on the list with 224 million ads served in September.

The report also highlights the rapid growth in usage of mobile Web sites and applications on new devices in the past year.

In September 2008, the Motorola RAZR was the top device in the US, and the iPhone was the only touchscreen device in the Top 10. In September 2009, the list of the top 10 devices includes five with touchscreens, six with Wi-Fi capabilities, and six with application stores. Apple now accounted for 25.3% of all requests - 16.9% for the iPhone and 8.4% for the iPod Touch.

Other highlights from the September 2009 report include:

Nearly every region of the world experienced immense growth in the past two years, with North America, Asia, Western Europe, Oceania and Latin America seeing a six-fold increase in traffic since September 2007.

Worldwide iPhone and iPod touch traffic increased 19 times from September 2008 to September 2009 in the AdMob network.

In September 2009 42 percent of requests in the US were made from Wi-Fi capable devices. 18 percent of actual US requests were made over a Wi-Fi connection in September 2009 compared to only 5 percent in September 2008.

Devices running on the Android Operating System (OS) accounted for 17 percent of smartphone traffic in AdMob’s network in the US in September 2009, up from 13 percent in August 2009. The HTC Dream (G1) was the number three device and the HTC Magic was the number 10 device in September 2009 in the US. As with the iPhone OS, much of the Android traffic in AdMob’s network came from applications.

Read the entire report here (.pdf)