Mobile advertising is emerging as an integral part of any marketing campaign these days. While mobile advertising is still in development, ABI Research forecasts that in the next five years, spending on mobile ads in the United States will nearly quadruple—to exceed $1.2 billion in 2015.

This month, Apple’s long-awaited iAd launched. And, one of the first companies to take advantage of nearly everything iAds and the iPhone has to offer, was Nissan. Nissan’s truly impressive interactive advertisement is engaging and lives directly inside the app. The Nissan Leaf iAd allows users to customize their car and learn about key features, including comparative miles per dollar.

So, where is the future of mobile advertising heading this year? It seems that not all advertisers and agencies have embraced mobile advertising and, instead, tend to stick with more traditional advertising methods such as TV and print ads. But with more and more users purchasing smart phones and using mobile internet, maybe 2010 will be the year that advertisers start seeing mobile ads as less of a risk and more as a chance to reach 45 million U.S. smart phone users.