“An advertising orgy”—that's how Al Ries, chairman of branding consultancy Ries & Ries, described the Super Bowl. And even b2b marketers are invited.

But Ries said companies that reserve ad space for the game and stop there are missing out on the spectacle's marketing power. “The Super Bowl is a bad advertising investment,” he said, “but it's a hell of a good PR investment.”

Super Bowl XLVI, which will air on NBC on Feb. 5, has sold out all of its advertising slots. Thirty-second spots reportedly sold for an average of $3.5 million each.

Advertisers during the game will include at least two b2b marketers: domain name registrar Go Daddy Operating Co. and job site CareerBuilder. “Both Go Daddy and CareerBuilder have broad appeal to a large audience, even though they are b2b companies,” said Jim Gregory, CEO of branding consultancy CoreBrand.

Go Daddy's strategy surrounding the game has been straightforward. For the past eight years, it has submitted an ad featuring a buxom woman, such as racecar driver Danica Patrick, to the network carrying the Super Bowl. When the network rejected the ad, as expected, Go Daddy publicized the “censorship” and generated media coverage.

This year, the company even got coverage when its ad was approved the first time around by NBC's standards and practices division.

Go Daddy said it will run two 30-second spots during this year's Super Bowl. The ads will feature Patrick, fitness trainer Jillian Michaels and the new Pussycat Dolls. One ad will promote Go Daddy's .co offering; the other will promote its services in the cloud.

Go Daddy said its 2011 Super Bowl spot triggered a 466% spike in domain name registrations in the first 15 minutes after the ad ran compared with the same period after the previous year's spot.

Ries said Go Daddy has taken advantage of the PR possibilities offered by advertising during the game. “It's the publicity that has told people what Go Daddy was,” he said.

Timothy Calkins, clinical professor of marketing at Northwestern University's Kellogg School of Management, also said Go Daddy has used the Super Bowl effectively.

“I would say Go Daddy and CareerBuilder have a very clear playbook that they use,” Calkins said. “Go Daddy develops advertising that is slightly controversial and generates a lot of discussion. It gets them an extraordinary amount of attention. Go Daddy is an example of a company using the Super Bowl to create its brand, and I think they've been remarkably successful at that.”

Calkins said CareerBuilder has done well using the game, although it has not reached the effectiveness of Go Daddy. “CareerBuilder has shifted a little over the years creatively,” he said. “They've changed their campaign several different times. Some have worked better than others.”

Last year, CareerBuilder returned to an effort featuring chimpanzees. The ad recently surpassed more than 790,000 views on YouTube, which is one venue—along with other social media sites—where Super Bowl spots can earn a return on their multimillion-dollar investment.

“It's really where some of the most creative efforts play out,” Calkins said of marketing initiatives beyond the game itself.