As smartphone sales increase every quarter, 4.2% in Q3 2009 according to IDC, the opportunity for more advertising impressions increases. Naturally Google wants to be the front-runner so they are buying mobile display advertising startup AdMob for $750 million in Google stock. From what I have seen AdMob has a handle on how to market, display, and provide metrics for mobile ads, while Google is just re-purposing ads that are normally displayed on PCs. Something tells me Google was less threatened  by AdMob and more worried about MSFT or Yahoo getting their hands on AdMob.

Who knows what will become of mobile advertising. The issue of location-based advertisements is already a major concern for some as our behaviors, data, and GPS location becomes a privacy issue. I am sure some will love the Subway coupons, but something tells me most people will hate mobile advertising. Regardless, if it becomes a hit Google will be leading the charge for sure.