Looking five, six, seven, 10 years ahead, advertising will become 15%, 20%, 25% of Microsoft’s business. As much as people have bones to pick with advertising, people much prefer an advertising-funded experience to one they pay for.”

–Microsoft CEO Steve Ballmer

Viacom has a new online advertising partner and–big surprise–it’s not Google. It’s Microsoft.

The entertainment broadcaster has signed a far-reaching, five-year strategic partnership with the world’s largest software company valued at approximately $500 million. Under its terms, Microsoft will buy ads across Viacom’s broadcast and online networks and license content from its MTV, Comedy Central, BET and Paramount Pictures properties for use on the MSN Web site and the Xbox 360.

In return, Viacom will adopt Microsoft’s Atlas AdManager digital-advertising technology and grant Redmond the exclusive right to sell remnant display-advertising inventory on its U.S. sites.

Quite the partnership, and one that may further in evolve in the years ahead. “This broad-based relationship will lead to conversations in other business areas,” Viacom CEO Philippe Dauman told Reuters. “What impressed me was the extent to which Microsoft is making the commitment–technological, financial and otherwise–to be a winner in this space.”

“Financial and otherwise,” indeed. As Om Malik notes, Viacom seems to have gotten itself quite a deal from Microsoft. “Viacom doesn’t have to spend anything and at the same time it is getting advertising dollars and more distribution for their content,” he writes. “I get a feeling that, going forward, this is going to become a template deal for all large media companies with content assets. For them it’s a green light to pillage Microsoft’s overflowing coffers. Deals like this will increase the pressure on Google to do similar ones with other content providers, mostly to thwart Microsoft’s advertising ambitions.”