U.S. is Key Android Market at the Moment

Worldwide mobile advertising requests from Android devices increased 97 percent from October to December 2009 and the big change since October is that Motorola devices have shown the greatest growth, undoubtedly because of Verizon's Droid launch late in the year.

AdMob says that in October, 98 percent of requests came from HTC devices.  In December, just 56 percent of requests were from HTC devices, 39 percent from Motorola devices, and five percent from Samsung units.

Increased device diversity: In December, seven devices generated more than three percent of requests each: the Motorola Droid, HTC Dream, HTC Magic, HTC Hero, Motorola CLIQ, HTC Droid Eris, and the Samsung Moment.

This is up from only three devices in October (HTC Dream, HTC Magic, and HTC Hero).

 The Motorola Droid is already the leading Android handset in the AdMob network and generated 30 percent of requests in December.

The U.S. market also, at least for the moment, the most-important global Android market. About 90 percent of Android traffic was generated in the United States in December, up from 84 percent  in October. The United Kingdom, Germany, France, and Canada were the other countries with some significant traffic.