caribguy - 4:15 am on Feb 17, 2010 (gmt 0)
I made a redirection mistake on one of my sites that caused http://example.com/robots.txt to serve a default robots file with the 'Disallow /' directive rather than 301 redirecting to http://www.example.com/robots.txt as intended.
The redirect worked fine for any other file except robots.txt but the result was that most pages were ranking for http://example.com/ rather than http://www.example.com/ - None of those pages would have a description, just the URL.
The redirect was fixed last Saturday, and today I'm already starting to see some pages rank properly. Impressive!