[Sem]

When your website gets crawled by Google, are all crawled pages available to "vote" for other pages or just the pages that actually get indexed into Google?

[Viktor]

I'd like to know also. My feeling is that not all pages votes, only the ones Google lists. I could be wrong of course, but that's the feeling I get. Also google doesn't crawl all pages so clearly some pages can't vote because google has never seen them.

[XP]

All pages that are crawled by Google "vote" expressed by an OGL. The vote may be worth more or less. The PR value of the vote depends on the voting page's PR, but the vote is worth, nonetheless, something, with a few exceptions. The vote's PR value is formulaic. The vote's specific value to it's candidate page generally depends upon various factors regarding the vote-receiving page.

[XP]

Furthermore, not all pages that are crawled by Googlebot are indexed. Nevertheless, they vote, and their vote normally has PR value. The exception is for either one of two reasons: 1. The receiving page's PR is such that the vote is immaterial; or, 2. the voting page is black-listed by Google.
As a practical matter, all votes are good (cary PR value) for the vote-receiving page; however, at what cost? In other words, if your page has a PR of 5, and an IBL vote from a PR1 costs an OBL from the same page, then this is not going to be, generally, a profitable exchange for the PR5 page. Still, while I can't demonstrate this, I believe that there may be exceptions to the foregoing.