A WebmasterWorld thread reports that several webmasters have noticed that even though they are redirecting their non www to the www version, Yahoo is still listing their non-www as the main result.
This comes even after months of redirecting the non www using a 301 redirect, permanent redirect, to the www version. Here are some comments from the thread:
www.example.com redirects to example.com and has done so for quite some time now. Yet when I do a search for a two word primary key phrase, Yahoo shows www.example.com. A search for my domain name returns example.com.
I was at #1 for a few years but lost some ranking in August for this search phrase. I'm not sure if the ranking loss is related.
Is it a backlink issue? Doesn't appear so:
I looked, and can't find any backlinks at all to non-www but the homepage shows up both with and without for different searches.
So what is going on with the latest Yahoo update? Good question.
Forum discussion at WebmasterWorld.