• by Mark Walsh  @markfwal, March 1, 2010

Unveiling new metrics in its latest monthly report, Millennial Media found that mobile campaigns are increasingly driving consumers toward mobile commerce, social media and search in the last several months.

Some 20% of campaigns encouraged users to make a mobile purchase from a Web retailer, 6% to engage in social media and 2% to search within ad creative itself or on a linked site in January, according to the mobile ad network.

Those types of calls-to-action in mobile are still not as prevalent as others such as downloading an application or click-to-call, which each account for 30% of actions, but they are starting to show up more and more in campaigns.

Millennial distinguishes m-commerce from another call-to-action category it has -- purchases and subscriptions -- as one that directs users to a retail purchase that involves a shopping cart feature (think Amazon) rather than carrier-based billing.

When it comes to targeting, reach remains the most important goal for mobile advertisers, with 38% launching for run-of-network campaigns. By contrast, only 4% use behavioral targeting. But that sliver commands by far the highest pricing, with a cost per engaged user (CPEU) of $1.38 compared to less than 20 cents for run-of-network. What's more, that cost jumped by 85 cents in just the last month, but is within the typical range of pricing for the segment, said Millennial.

The mobile ad network's January report also looked at how brand campaigns on mobile compared to those on the desktop Web across 10 major consumer categories. Based on research from Insight Express, it found that brand impact was higher on mobile than online in categories such as retail, travel, automotive and technology across traditional metrics such as aided and unaided awareness and purchase intent. The biggest difference was aided awareness in retail, which indexed 14 times higher in mobile than online.

But it's important to consider that InsightExpress reached its conclusions by comparing norms derived from its database of more than 1,000 online ad effectiveness campaigns with only 100 mobile campaigns.

Millennial also reported that Apple in January remained the top device maker in its network, accounting for 36% of impressions -- up about 12% from last month. Devices running on the iPhone and Research in Motion operating systems alone generated 77% of Millennial's U.S. smartphone impressions, and smartphones overall generated 58% of U.S. impressions.

In a related report Monday, Web analytics firm Quantcast said the iPhone OS accounted for nearly 64% of mobile Web activity in North America in February, trailed by Android (15.2%), RIM (9.2%) and all others (11.8%). While the iPhone remains dominant, its competitors are starting to eat into its huge lead.

In the last year, Google's Android has increased its share 95.3% and RIM (BlackBerry), 7.5%, even as that of the iPhone OS has shrunk 10.2%. In the last month, RIM has seen a nice bump, growing share by 13.8%, while Android has gone up 8.3% and the iPhone has declined 3.2%.