What is better to use with search engines and PR in mind?
http://www.domain.com or http://domain.com

I am talking about the path settings in the configure.php.

I am wondering what the impact is for the search engines and if this matters at all. As far as I know, consistency is the key. Meaning, link exchange should use the same format so the PR goes to one version of the two. Any other thoughts why one should use one or the other?