Way back in Feb of 2007 I migrated a section of one of my sites to a sub domain. During the move I accidentally broke a series of sidebar links for all of about an hour, during that hour they had <webURL> type tags attached.
Fast forward to 3.5 years later some scraper site has gone in and copied, verbatim, my entire site from that one hour period including broken sidebar links. All of the links point to my site, of course.
Google Webmaster Tools is reporting this to me as one instance of MY site having a "page not found" last linked from my home page sidebar in 2007 and dozens of missing pages all linked from this scraper site.
What I don't get is that the links are broken, they lead to 404 error pages, yet GWT still assigns them as missing from MY site.
This, combined with the clickable "cache" version of my entire site on a Google.com domain, have me feeling that it's time to add a "noarchive" meta tag to my site. I can't see anything that says I shouldn't at this time. I already implemented a frame buster script that shot my traffic up 11% on an image heavy site and unless someone can point out an obvious reason NOT to remove archived copies of my site... is it time?