Microsoft yesterday announced (https://web.archive.org/web/20120611102727/http://blogs.msdn.com/livesearch/archive/2008/05/23/book-search-winding-down.aspx?) on the Live Search Blog that their Academic Search (https://web.archive.org/web/20120611102727/http://search.live.com/academic/?) will be closed next week.
And Google Scholar (https://web.archive.org/web/20120611102727/http://scholar.google.com/?) still has shortcomings, including the lack of special limitation features that are found in PubMed. A more detailed comparison of PubMed and Google Scholar can be found in this paper (https://web.archive.org/web/20120611102727/http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=17971893?).
Does this announcement simply reflect a shift in strategy at Microsoft, or is academic search no longer interesting to Microsoft, Google, etc.?