Though it lags behind Google and Yahoo in online advertising revenue, Microsoft is flexing some newly-formed online ad muscle by putting ads into its MSN Mobile portal on cell phones.

The software giant, which also struck an ad deal with CNBC.com, says the addition of ads to the MSN Mobile service is part of a long-term strategy. "There's a realization that mobile advertising right now is a relatively small percentage of the pie today, but a huge opportunity in future years," Phil Holden, a director in Microsoft's online unit, says in this Seattle Times story.

To be sure, Google and Yahoo are monkey-stomping Microsoft when it comes to online ad revenue: Microsoft reported $487 million in ad revenue in its most recent quarter, a 33 percent increase. That's far behind Google and Yahoo, which reported $4.2 billion and $1.5 billion in ad revenue during the same period, respectively.

Nevertheless, you can see Microsoft using newly acquired tools, including online ad company aQuantive, which it bought for $6 billion in cash, to catch itself up to the competition. AQuantive helped create the free MSN Mobile portal system that runs inside Web browsers on a variety of mobile phones and software, including Microsoft's Windows Mobile operating system. It provides access to news, sports, weather and other content.

Meanwhile, Microsoft became the exclusive third-party provider of advertising on CNBC.com, the web site for financial news channel CNBC. The CNBC.com site has 2.6 million unique monthly visitors. By contrast, Microsoft has access to 50 million active users through it advertising deal with Facebook, the social networking site.

The backdrop to all of this is the future, and the future, according to industry observer eMarketer is "mobile users as walking production studios:

"User-generated and shared content will account for one-quarter of the world's entertainment within five years, according to Nokia's "A Glimpse of the Next Episode" report, conducted by The Future Laboratory.

"Nokia said that nearly three out of 10 tech-savvy mobile users ages 16 to 35 blogged, and nearly as many used social networking sites. The company also said that these early adopters consumed a lot of entertainment on their mobile phones.

"As a result, argues Nokia, mobile users are poised to consume more user-generated entertainment on their handsets in the future."

They are poised to consume a lot more mobile advertising, as well.