First of all, I'm going to say I know little in this area. I've done some
preliminary research about search indexing (Google's) and investigated a
few OPAC robot.txt files. Now to my questions:

   - Can someone explain to me or point me to research as to why local
   library catalog records do not show up in Google, Bing, or Yahoo! search
   results?
   - Is there a general prohibition by libraries for search engines to
   crawl their public records?
   - Do the search engines not index these records actively?
   - Is it a matter of SEO/promoted results?
   - Is it because some systems don't mint URLs for each record?

I haven't seen a lot of discussion about this recently and I know Jason
Ranallo has done a lot of work in this area and gave a great talk at
code4lib Seattle on microdata/Schema.org, so I figured this could be part
of that continuing conversation.

I look forward to being educated by you all,

Tod

-- 
Tod Robbins
iSchool GSA Crew
MLIS Candidate 2012
University of Washington