A study by Ivor Hewitt initiated a discussion among the SEOs (Search Engine Optimisations) about whether MSN search results favour IIS-hosted sites. While the early methodology of Ivor's study is far from perfect, it does show a tendency of MSN search result returns a larger portion of IIS-hosted pages.
Should educators care about such discussion? Probably not as much as the SEOs. But if we are promoting our students to understand information search, resource discovery in particular, then it would be a good topic to monitor.