I'm building a list of backlink sources for a herbal niche site, when I came across this: https://auth.gardenweb.com/members/hybridsage Code (markup): (I posted the whole url because I don't care if you guys steal it) That's not my profile but as you can see the demo web link is a do-follow one. The "gardenweb.com" site has a PR of 7 but it refers to that subdomain for member profiles. I do not believe they allow signatures, but any links in the forum are also do-follow. I don't like making posts specifically to promote a website, because that's just spamming in my book. I'd rather leave a signature or a profile with a link in it. What kind of linkjuice would that N/A subdomain give a link?
In general, a domain or subdomain that has a n/a PR means that it just hasnt been ranked yet, or doesnt meet the criteria to be a PR0 or above. This never really deters me, at the end of the day, diferent backlinks are always a good thing from a variety of PR types.
PR n/a is considered on newly build websites or blogs. As such websites or blogs are not yet crawled and their links aren't found by Google.