Of course, the conventional wisdom is often wrong -- and never more so than right now. The imperative to boost ROI, rapidly, gives social media a tremendous opportunity to flex its muscles and send doubters packing. Even in a time of retrenchment, eMarketer projects that U.S. online social network ad spending will grow 55% this year.

Indeed, the social web has value not only as a medium that delivers measurable results, but one that also serves as a resource for gaining insights marketers can use to make all of their advertising (TV, print, online) more effective, to boost returns across the board.

Social media is by definition packed with actionable information. Advertisers with access to relevant analytics can pinpoint their audiences and learn more about them to get a picture of who they are and what they want. Need to reach boomers who are interested in fine wine? How about New Yorkers who like Jamaican vacations? No problem. It's a snap to aggregate more information and optimize ads along the way, fine-tuning reach and making campaigns more effective.

That's a very big deal -- a tonic for marketers and agencies in a time when "traditional" online may have hit a wall.

But as important as such targeting is -- and it is significant -- there's another valuable aspect to social media: the level of consumer engagement with the social "medium" itself (measured against any other medium -- TV, radio, print or even online 1.0).

Social sites feel like home to increasing numbers of people. They want to be there, and there is nothing casual or quick about their relationships to those sites. They're not passive observers -- they're active participants. They're playing games, sending messages, reading blog posts, pinging their Facebook friends, commenting on someone else's photo, and the list goes on. They're typing, conversing, reacting, and creating - round the clock. They're engaged.

Engagement may be the most powerful (even revolutionary) aspect of the social web: the degree to which the medium has a life of its own -- one that is more tightly intertwined with the individual's "offline" life than anything preceding it, digitally.

Combine these two characteristics of social media:

• the access to enough data about demographics, traffic, interests and social actions to pinpoint a target audience and understand them better, and

• the attention that consumers give to this medium while they're there.

For marketers, that means the potential to gain unprecedented levels of information about audiences and messages. How? By offering people incentives to award some of that attention to the brand at hand.

Here's the Incentive

On the social web, audience members are already on the edge of their seats. Incentives help capture attention. The art then becomes leveraging that attention to increase ROI.

The idea of incentives is certainly time-tested. Most consumers have shared contact information for the chance to win an iPod, a trip, a car, or (in a weaker moment) a timeshare -- or completed a brief survey to walk off with a free lunch. The online world follows the same rules. The lure is eternal, even if it doesn't involve filling out a form with a stubby pencil and stuffing into a Lucite box at the local shopping mall.

The principle of incentives operates just as well in the virtual economy, and that's the new opportunity that engagement with the social web brings to marketers. Offer game points, gold for virtual pets, or a free gift, in exchange for taking a certain action.

It's in this action where the real gold lies, thanks to those two characteristics of social media. No longer are the actions limited to collecting a consumer's mailing address or surveying for opinions that aren't tied to any demographics.

The action is to view the ad (banner or video) and answer a few questions about it.

The incentive is whatever the publisher is offering as a reward (the points, the gold, the gift, anything).

The payoff to the marketer is intelligence that helps increase ROI within all types of advertising.

Surveys can be designed to measure consumer perception:

• Awareness - Who has heard of the brand?

• Attitudes - How do people feel about the brand?

• Favorability - Do people like the brand?

• Intent - How likely are people to purchase these products or services?

• Preference - Do people prefer the brand or products over others?

The right analytics partner can couple those results with user demographics like age, location and gender, along with interests and social actions. Take, for example, anonymous Consumer A -- a 33-year-old man who lives in Kansas City, reads GQ, plays Scramble on Facebook, and says he is "very likely" to see the next James Bond movie.

That's a hefty amount of actionable intelligence for any company. In this hypothetical, using aggregate (and always anonymous) audience information, the movie studio might discover that while it's been concentrating ad dollars on reaching both coasts, perhaps there's value in targeting consumers in the Midwest who match certain demographics.

Beyond its real value as an advertising channel on its own, the social web is becoming an effective laboratory/extended focus group for companies to discover who their audiences are and how to more effectively reach them - from any medium.

The social space is evolving into an environment that offers advertisers an efficient way to understand audience behavior and perception - and to reach people with precision targeting never seen before. There's no better incentive to get social.

This commentary is insightful. I recommend it to others.