Edited by author 04-08-2008 04:30 PM
In the "Automatic Identification of User Goals for Web Search" paper: for the anchor-link distribution, there is a fair assumption that there isn't a single authoritative site for most informational queries. However, in the future this could slightly incorrect, if sites like Wikipedia are more embraced (or for that matter Google's Knol gathers momentum, as it has the explicit objective of being the first site that users will want to visit to get information on a subject!). I wouldn't expect it would dramatically skew the distribution of links, but it suggests that user-click distribution might be slightly more robust.