The monthly Admob Metrics Report was released yesterday, and had some really great highlights for mobile web developers. Mobile web usage is literally growing by leaps and bounds each month.

Again this report is not a measure of phone usage, but of data usage measured by impressions over the Admob advertising network. Overall this report gives web developers a great idea of who is using the mobile web, what phones they are using, and where they are located geographically.

• Worldwide requests were up 9% over last month, to nearly 6.3 billion
• North American requests were up by 20% over last month, thanks to a big boost after Christmas
• The iPod touch is the big winner in December, with requests growing by 340% worldwide. In July, the device generated 18 million requests, and in December it generated 292 million requests.
• 70% of iPod touch traffic comes from the US, and Christmas was a difference-maker. In the seven days after Christmas, requests were up 240% compared to the seven days before Christmas.
• Smartphones continue explosive growth, now accounting for 33% of worldwide requests. The Symbian and iPhone operating systems now make up 73% of smartphones worldwide.

The following stats are based on 6,290,653,484 requests:

Top 5 Countries

1. United States (45.8%, +3.8%)
2. Indonesia (13.2%, -3%)
3. India (7.0%, -0.9%)
4. United Kingdom (3.4%, -0.9%)
5. Philippines (2.7%, -0.1%)

Top 5 Worldwide Handsets

1. Apple iPhone (10.8%, +4.4%)
2. Apple iPod Touch (4.7%, +3.2%)
3. Motorola RAZR V3 (3.4%, -0.3%)
4. Nokia N70 (2.4%, -0.3%)
5. Motorola KRZR K1c (1.7%, -0.2%)

Top 5 US Handsets

1. Apple iPhone (16.2%, +6.3%)
2. Apple iPod Touch (7.1%, +4.8%)
3. Motorola RAZR V3 (6.4%, -1.1%)
4. Motorola KRZR K1c (3.7%, -0.7%)
5. Motorola Z6m (3.4%, -0.3%)