Serendipity - 8:05 pm on Jun 24, 2013 (gmt 0)
The plugin's page states: "Increase the number of pages indexed by adding a special link to search results"
The requested urls are getting 404 not found error (as shown in Google Webmaster). The number of these errors are decreasing though.
Also, to combat this I have installed a plugin which tries to locate any posts with similar words and redirects to that post before it generates the 404 error.