An interesting study conducted by De Vos & Jansen Market Research and Search Engine Mediabureau Checkit shows a 10% difference in way Search Results are transversed between Buyers and Informational Searchers.

This would be even more interesting if we could get the analytics to track each search session on a site and determine the percentage of searches that are informational vs. buy oriented (when both options are present).   The conclusions of the De Vos & Jansen report are:

1. Consumers view a search result for 1,1 second.
2. 98% views the organic search results.
3. 96% views the top (three) sponsored search results.
4. 31% views the sponsored search results on the right.
5. Buyers view more search results (10) and take more time to view the results (11,4 seconds). They also focus on familiar brand names.
6. Information searchers view less search results (8) and spend less time on a result (9,4 seconds). They pay more attention to contents than to brand names

I think people looking for information, according to this study, on average, will spend less time searching, look at less search results and those who are more intent on finding something in particular (on your site).

I think it would be possible to break down the search behavior of visitors searching on a site with even this much information - but you would have a lot of search behavior being undetermined; I think another criteria needs to be added - maybe the length of the search query (a longer query is a more deliberate searcher - therefore falling closer to a transaction query).

Transactional Searcher spend an average of 1-2 more seconds looking at a search result - another way to segment Search Intent:

"….Average viewing duration per result: 1,1 second

Advertisers should communicate within the consumer in a very short period of time. The average viewing duration for a search result is 1,1 second. The average viewing duration for an organic result is 1,3 seconds and for a sponsored result at the top 0,8 second. The sponsored results on the right were viewed only short(average 0,2 seconds)."

Seems like we have all the necessary information, from a Web Metrics perspective - to determine Search Intent - in fact, the Search Engine itself, should be able to track this and report on it.

Behavior is the same across Search Engines - and these cool Diagrams are some of the neatest I've seen regarding how people Search.

Look at the imprint of an "informational" or "casual" searcher:

And compare it to a "Transactional" Searcher - below:

The Search Behavior is really, really different - not that subtle at all when looked at visually - this is within the realm of a site search engine - and certainly, within Google's power to decide.  I would think this is worth tracking - no question of it.

Not only that - but if a searcher arrives on your site from Google or Yahoo with this profile (Transaction based) vs. Information based search profile that information would be nice to report in Google's Webmaster Tools - again - it's totally doable.

I hope this insight gets picked up by the Search Engines - as the major Search Engines are all planning to support Google Web-master's tools (aka, Sitemaps).