Proportion of total fixation duration for each
component of search results, broken down by task type and
snippet length. As snippet length increases, the relative
proportion of gaze devoted to the URL decreases.
Jacob Nielsen reveals in the latest emailed Alertbox that SE users spend nearly a quarter (24%) of the time staring at web addresses (URLs).
Edward Cutrell and Zhiwei Guan from Microsoft Research ... used Microsoft's own search engine (fair enough), but their results match what we found in our eyetracking which included the current market leader as well as the #2 search engine in addition to Microsoft.
Users have evolved a firm model of search behavior which they apply across search engines, which is why it's probably a lost cause to make a non-standard search user interface.
Searchers are particularly interested in the URL when they are assessing the credibility of a destination.
This finding confirms the importance of human-readable URLs, which I discussed 8 years ago.
Another interesting finding from the MSR paper is that longer summaries (or snippets, as they call them) are useful for informational queries, whereas short summaries are best for navigational queries where users are looking for a pre-determined site or page.
Full academic paper (warning: PDF).