Millennial Media has just published its monthly S.M.A.R.T report, or “Scorecard for Mobile Advertising Reach and Targeting,” that gives insight and stats into the mobile advertising landscape as seen from Millennial Media- a leading mobile ad network in the US.

The report focuses on user engagement, mobile presence and device use profiles with an emphasis on a new concept known as Cost Per Engaged User or CPEU. GoMo News had an excellent analysis on what CPEU entails and how Millennial Media is using it as a new business model.

GoMo characterizes CPEU as the process in which the advertisements are displayed for free, but the engagement with the advertisement is measured and billed. Instead of CPC (cost per click) or CPM (cost per thousand) the advertiser only pays depending on the interaction the user has with the advertisement.

In terms of engagement, Millennial conducted a study on users’ level of satisfaction while engaging with five different mobile activities across feature phones, smartphones, and computers. On four out of five activities, smartphones ranked anywhere from 4% to 9% higher than on a computer. Interestingly enough, while engagement via smartphones is higher than on computers, browsing the internet on a computer ranked 2% higher than on a smartphone- proving the concept of CPEU is valuable to marketers.

When it comes to devices, Apple gained additional traction in Millennial’s network and pulled within 2.48% of Samsung, the current leader. iPhone and iPod Touch impressions increased another 15% in August, and Blackberry and Samsung continued to compete for the top five mobile phone spots, as Blackberry Curve and Pearl grabbed #2 and #4. Wi-Fi aided mobile content consumption, increasing 1.26% month over month, and dominated the U.S. Carrier Mix with 26.15% impression share.