What kind of opportunities - and risks - will this allow? We've decided to spend an article discussing the question.

What they're looking at In a typical Web search, your eye scans down the text results one result at a time. But with image search results, you don't have to read, you only have to see, and seeing takes less time than reading does. Plus, you can also make sense of a montage of many pictures, all of them of the same thing. It's hard to make sense, quickly, of lists of texts describing Web sites. Which means that, in an image search, you're more capable of processing many results at once.

That means that image-search ads can address the entire results page in a way that image search ads can't. A good example comes from Google's image results for the word "shoes" (at the time of this writing). Google gives 19 fairly ordinary pictures of shoes, and one result of two men wearing enormous wooden clogs. Granted, the fact that this picture is in the second image position makes it all the more noticeable, but even so - where do you think your eye goes? Had that picture been an ad, it could have attracted a lot of attention for a product. Had it appeared amongst text results, it would have gotten lost in the letters.

Why use image search? In text-based search, people aren't looking for what they find in the search results listing; they're looking for the Web sites that the search results lead them to. Once they see the search results links, people proceed to the Web site. The search engine is an intermediary site.

Sometimes image search works the same way, but rather than using text to find the site you want, you use pictures. If you're shopping for clothes, furniture, or dinnerware, you might prefer an image search for any one of those things as a way to find a Web site that sells products tailored to your taste, because text descriptions might be a harder way to find the best site quickly.

Searchers might use this kind of image search because they know what the thing they're searching for looks like, but they just don't know what it's called. An image search might help them find it quicker. And, if you already understand the product you're looking for that well, there's a good chance you're already far along in the purchasing cycle. So you're a good lead.

That's one way people use image search. Often, though, people use image search because they're looking for an image. Maybe they're trying to get ideas or images to put on their own Web site, maybe they're interested in learning what something looks like, maybe image search is just their way of surfing for nice things to look at. For these searchers, image search isn't a medium to another Web site - it's a destination in and of itself.

The fact that different searchers could be using image search for such drastically different things means that, on any image search ad you run, you also run a high risk of getting click-throughs from searchers with no interest in buying your product. In a pay-per-click ad campaign, that can be a big drain on your resources, so advertiser beware.

One way to make the whole scenario less problematic, of course, is to make what you're advertising for that much clearer, so you'll get fewer people clicking on your ad in error. But that still won't stop the people who click on an ad without looking at it carefully. And that's a high percentage of ad viewers.

So what all this means, for now, is that there's a huge opportunity in image search ads just waiting to happen. There's also a huge risk. Which one will end up being greater? Only time will tell.

David Pasternack is president and co-founder and Bill Wise is CEO of Did-it.com, a search engine marketing agency. For more information, visit www.did-it.com.

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