Blog publishing services typically propagate updates about new posts from blogs (ergo, new blogs too) by pinging or publishing a changes.xml file. But what none of the services provide is an "un-ping" -- blog indexing services such as Technorati don't know when a blog has been deleted from a service. I noticed this today when I found http://blogtrarian.blogspot.com/ participating in a link farm infesting Blogger's service. This can happen because Google's Blogger recycles URLs; when a blog is removed from the system, the URL is freed for reuse.
That particular URL is one that dates back to 2004, it was dormant for several months but just came to life recently with spam. The historic posts (until August 2005) look like normal blogging fare but the recent posts are clearly just splog content. We'll have to work on "un-pinging" so it's easier to distinguish dormant blogs and dead ones.( May 06 2006, 03:13:14 PM PDT ) Permalink