Most recent entries:

• Google's Search Results 404ing | April 25, 2011
• Google's Custom 404 Page Robot | March 2, 2011
• Not Only Are 410 Response Codes More Permanent, They Are Faster | April 30, 2010
• Google Now Treats 410 Status Code As "More Permanent" Than 404 Status Code | October 27, 2009
• Google Enhanced 404 Feature Gone? | July 8, 2009