Mobile advertising marketplace AdMob has released metrics on its iPhone ad unit. The company says it has seen an explosive increase in iPhone traffic over the past few months. Since the announcement of the iPhone ad network back in July 2007, AdMob has served over 249 million iPhone ads worldwide.
AdMobs iPhone network served 51.8 million ads worldwide in June, a 32% increase on the 39.1 million ads served in May. In the US, AdMob served 34 million ads in June, a 31% increase on the 25.9 million ads served  in May. The top countries for iPhone ad traffic are the US, followed by the Philippines, the UK and France. Major advertisers that have run iPhone ads exclusively with AdMob include Land Rover,  Jaguar and Fox
Popular consumer features of the iPhone ads include the store locator with integration of Google maps, and the click-to-call and click-to-play video features.   
The usage patterns on next generation devices are terrifically exciting, says AdMob CEO, Omar Hamoui. We served nearly a quarter-billion ads on the iPhone in its first year in the market. We expect that the iPhone and devices like it will be an enormous catalyst for the mobile media business.
AdMob notes that the iPhone ads leverage the networks targeting capabilities, enabling advertisers to reach users based on their behaviour and demographics. Initial data show users typically favouring weather, news, entertainment and sports-related mobile sites.