John Brandon has a piece at Network World and pcworld.com titled "Google Can't Find Everything" which lists five aspects of search that Google doesn't do as well as they might do.

http://www.pcworld.com/businesscenter/article/160065/google_cant_find_everything.html

   • Image Searches

   • Database Searches

   • Searching Speech

   • Searching Printed Literature

   • Searching Online Books

There is also a link to an earlier article by Tom Spring about ten Google flops.
http://www.pcworld.com/article/146101/top_10_google_flubs_flops_and_failures.html?tk=rel_news