Question : does missing a <a rel="nofollow" href="http://WWW" target="_blank">WWW</a>. in a link URL affect SEO?

I have a client with a link to http://theravive.com which works just fine, but what I would like to know if missing the www portion may have some impact on ranking algorithims.  Do all search engines "think" that http://mydomain.com is the same page and same thing as http://www.mydomain.com?

Answer : does missing a <a rel="nofollow" href="http://WWW" target="_blank">WWW</a>. in a link URL affect SEO?

Here is a good discussion on this very topic.  You will seeing varying info so you will need to ultimately decide...

http://drupal.org/node/50743