Missing WWW in Google Listing

Does it affect PR or not?

[phpmaven]

My site's url is currently listed without "www" ahead of my domain. Does Google consider "www.mydomain.com" and "mydomain.com" to be different? Would they assign different PR values to each version?

Virtually every incoming link I have lists my site with "www". When I pull up pages from my site using either version, the PR doesn't change. I'm assuming that Google is counting my incoming links as I have a PR of 4.

Does anyone have any insight on this?

Thank you

[EliteWeb]

I see sites listed without www when a larger site links to a site without the www. google will index it without the www and with the www and because its on the same domain and unique content i think it picks the one with the highest amount of links to it that have the higher PR and the most people linking to it without the www.