In 2012, nothing’s quite as valuable to online advertisers as attention.

But measuring attention online is an uncertain science: How can advertisers ever know who for certain how many people actually see their ads? That’s been the central issue for online advertsing since basically the beginning of the commercial web, and yet it still remains imprecise.

EyeTrackShop, however, says it’s figured it out. Its realCPM platform intends to give advertisers a better idea of whether people are seeing their advertisements. And to do that it must track exactly what web users are looking at onscreen.

At the core of this effort is the average webcam, which lets EyeTrackShop work with survey respondents easily and without the need to call them all together to one location.

But why eye-tracking at all? For EyeTrackShop president Jeff Bander it’s understanding one ocular truism: The eyes never lie.

“Eye-tracking isn’t an opinion. You can’t ask questions to get the kind of answer that eyeballs can give you,”Bander said.

For Bander, any attempt to measure online attention solely via survey is doomed to failure. Too much is going on under the surface, too many unconscious tendencies that survey respondents are not actively aware of.

“What people say they notice is very rarely accurate,” Bander said.

The basic problem is that just because an ad appears doesn’t mean that a web user has noticed it, even if they have technically ”seen it.”

Advertisers know this, of course. But lost on them so far has been the capability to separate the ads that are seen from the ads that aren’t. The mission behind realCPM is to give agencies that capability by allowing them to create online panels of web users on-the-fly.

As a result of all this, web ads get smarter, which in turn means that advertisers are spending money more wisely on ads that actually work. It’s good news, too, for publishers, who can optimize their website to create more valuable advertising space.

Of course, you can’t say anything about advertising nowadays without saying mobile in the next breath. Fortunately, EyeTrackShop plans to to expand into mobile before long as well.