If a forum has a pagerank of 4, yet I make a thread and the EXACT url for that thread has a page rank of zero, do I get page rank points from the homepage or from the exact URL? Also, everytime I post on a forum with my sig, does that count as a new link?
I notice sig links on DP don't count.. anyone else? As for your question, its a bit of both I'd think. You get PR from quality inbound links pointing in to that "new" forum thread. But I think you may also get PR that passes through the domain into all subpages? Well thats my experiences anyway. Feel free to correct me where I am wrong
You only get the PR distribution from that page that linked out (since it is a page rank). Therefore, the new thread with PR 0 will distribute its PR to the outgoing links on that page. I believe that the link in your signature count towards a new link (read somwhere but couldn't find that thread..)
Just because a page has toolbar PR0 it doesn't mean its real PR is 0. As long as the page is not an orphan page (if its a forum it won't be) then it will get PR eventually. Sig links do count as backlinks and pass PR. Why wouldn't they? Google can't discount all links otherwise nobody would rank for anything.
In my opinion Google PR has much more to do with page content than it does with inbound links. The reason that I say this is that I have many pages that are PR 3 and 4 with almost no inbound links. I also agree with the above that any PR value would come from the actual page that the link appears on and not the home page of the site in question.
There are two cases for this scenario: 1. Search Engine does not show all the backlinks.. try MSN and yahoo to see if there's any. 2. The PR is fake, try the following tool to determine: http://www.namepros.com/fakepr.php