Website URL

URL and redirect with respect to ranking

[SEOPimp]

Hi Everyone,

I would like to know if there is a difference between having your domain name redirect to the www version or not.
For example if my site is www.BlueWidgets.com
Would you recommend I redirect everyone coming into my site from BlueWidgets.com to www.
The top people for my keywords all redirect to the www, while I am yet to do so.

BTW, I don't see a difference in my PR from the www version and the one without.

Thanks for all your help.