walkman - 4:27 am on Apr 19, 2011 (gmt 0)
Read this from Matt in 2008 [mattcutts.com...]
Matt Cutts – Google Not prepared, but informal remarks. High order nits: what do people worry about? He often finds that honest webmasters worry about dupe content when they don’t need to. G tries to always return the “best” version of a page.
and compare to what we think Panda does. Maybe a few months after losing our shirts we may find out that 404 should have been used