Website Subdomains

I wanted to know if having multiple subdomains on one website will affect PR?

Each will be a seperate domain with seperate PR I believe.

that's what I thought, but wanted to ask to be sure.
thanks ;)

Yep. See http://www.psychlinks.ca http://forum.psychlinks.ca http://directory.psychlinks.ca http://blog.psychlinks.ca etc.

Minstrel, do you think its better to do it that way?

I think there are pros and cons to subdomains vs. subdirectories vs. separate domains. I decided to do it this way with the Psychlinks network partly because there are advantages especially within Google (or at least there were prior to Big Daddy - these days I don't know what's good and what's bad with Google).

There's a great article on this:

Folders vs. Subdomains (http://www.highrankings.com/issue105.htm)
By Catherine Parker, Quirk Marketing, from the Highrankings.com newsletter

Minstrel, do you think its better to do it that way?
When I decide on the subforum issue it has more to do with the amount of promotion/SEO I can do for that section of the site. If you are looking to just add a forum where an existing user base exists and the main site is heavily SEO'd as it is, I just add it as /forums/

If I am going to invest a bit of time in getting links and general promotions I go with forums.ddddd.com

Also, think about if you are ever going to sell it on its own. If there is even a chance, you are better to make it a subforum (even better is a whole new site but thats not part of the discussion)