Ever since the advent of mobile data, the industry has debated whether the handheld browser could be used as an advertising medium. With such limited on-screen real estate, less-then-optimal navigation options and the sheer number of different devices to support, the phone screen hasn’t historically been a magnet for Internet advertisers. But recently the mobile Internet has become a much more viable vehicle for advertising and marketing. The biggest sign that the mobile Web has come into its own is probably the fact that Web analytics giant Omniture has actually begun to measure it.

Omniture is best known for its SiteCatalyst Web measurement tools, which track Internet users’ usage patterns across the Web. That data is, in turn, used by its customers not only to better understand their customers but as the basis for the rates they charge for online advertising. This summer, Omniture extended its comprehensive suite of SiteCatalyst analytics and marketing campaign tools to the mobile Internet.

While Omniture has offered some mobile measurement capabilities in the past, this is the first time it has integrated SiteCatalyst’s full capabilities into wireless, allowing site owners to see who is accessing their content and their advertisers in turn to market to them. Why the sudden interest in the handset as a marketing tool?

According to Omniture senior director of marketing Matt Langie, there is no one reason, but a combination of them. The iPhone is one of the biggest, delivering a rich browser experience to the handset, but the iPhone’s penetration is still small compared to the billions of Web-enabled devices in the market today. Another reason is the startling growth in data traffic over 3G networks. But perhaps the biggest catalyst for mobile marketing has been the realization that the mobile phone is intimate yet ubiquitous means of reaching customers, Langie said. “Our customers are saying to us that mobile is important to them,” Langie said.

Research firm Gartner has projected mobile advertising spending will reach $2.7 billion globally this year, jumping a full $1 billion above 2007 levels. By the end of 2011, Gartner expects that market to grow to $12.8 billion. Furthermore, that impact could be disproportionately higher in the U.S., due to its higher levels of mobile Internet usage. Driven in part by the greater availability of 3G, but mainly attributable to the ready availability of cheap unlimited data packages, 40 million mobile subscribers are active users of the mobile Internet—roughly 15.6% of all U.S. subscribers. Compared to the U.K. at 12.9% and Italy at 11.9%, a far greater percentage of U.S. mobile users are surfing the mobile Web and exposing them to the advertising embedded within.