Getting Blacklisted Because of Non-WWW Form of Website

[mtaunk]

I have a website that is a PR7 and there are two versions of the site being indexed, one is the 'http://www.website.com' and one which is the 'http://website.com' form. The non-www form has a PR5. Is it possible for Google to blacklist our website because of this.

Also, if various PR8 and PR9 websites linked to the 'http://website.com' site, could that potentially expedite the process to get us blacklisted?

[Marval]

The answer is "sorta" yes - sorry - you wont get "blacklisted" - however you will incur a small dupe penalty which (at least in my case two years ago) can cause loss of ranking in the SERPs. I assume you are using relative and not absolute linking on the site.
I would first check (again assuming you are on an Apache server of some kind) the Servername directive in the httpd config file to ensure it is set for a default of the www.domain.com and not domain.com
Then take a quick gander at this thread on the same problem [webmasterworld.com...]
for the rest of the fixes.