Scoble points to some fascinating research results on web search - the bottomline is, if you don't show up on the first page of results for a search that should find you, you don't exist. If you aren't at the top of the list, it's nearly as bad:

Professor Thorsten Joachims and colleagues at Cornell University conducted a study of search engines. Among other things, their study examined the links users followed on the SERP (search engine results page). They found that 42% of users clicked the top search hit, and 8% of users clicked the second hit. So far, no news. Many previous studies, including my own, have shown that the top few entries in search listings get the preponderance of clicks and that the number one hit gets vastly more clicks than anything else.

There's more - they tried some hidden manipulation of results to see what happened:

What is interesting is the researchers’ second test, wherein they secretly fed the search results through a script before displaying them to users. This script swapped the order of the top two search hits. In other words, what was originally the number two entry in the search engine's prioritization ended up on top, and the top entry was relegated to second place.

In this swapped condition, users still clicked on the top entry 34% of the time and on the second hit 12% of the time.

Meaning, an awful lot of people (a solid plurality) hit the first link without really examining it. Think about what the means in the context of my earlier post on google bombing. Now, bear in mind what this means if people haven't heard of your company, but are interested in a product or service you provide: it means that you are completely invisible unless you get yourself to the top of the list (or at least the first page) for relevant search terms.