Call me a n00b if you will, but are all backlinks given the same "weight" by google page-rank algorithms? Arbitrarily, say one site has a backlink to www.cia.gov and another has a backlink to www.geocities.com/crazyman6/bigfartshahahahahha.htm, are both links weighted equally and the page ranks sandwiched right togeather? the logic of the backlink system doesn't always make sense to me...
No. 1. If you get a backling from a website which is related to or in the same category/industry/topic you get much more PR. 2. The above + PR of source website = even higher.
that sounds logical at least.... but im talking primarily about just how major the back-linked site is. Does that bear any influence on PR?
I never saw any proof of that assertion... Maybe you get more benefit (better ranking) if the links come from a topic-related site. I'd be interested in an example, please.
I'm sorry, but you don't know what you are talking about. PR is a simple mathematical calculation based on the PR of the page issuing the backlink. It has nothing to do with theme or content or URL. Now the value of the backlink as a contributor to the relevance of the page, and its placement in the SERPs, is an entirely different issue. If you want to try to understand PageRank a little more thoroughly read my Google PageRank & How to Get It article.