Forum Moderators: Robert Charlton & goodroi
1. depends on forum's trust profile with google
2. cgi/redirect "click counting" scripts on outbound links can nullify any PR vote
3. the rel="nofollow" attribute can also nullify the PR vote
4. signature links seem most ignored (possibly just dampened) but links within the post content seem to do better.
The keyword and theme relevance influence of backlinks can pass, even if PR doesn't. I would like to think that topical relevance matters, but I sometimes see the odd example that makes me wonder about that. This could mean that a high percent of forum links on non-related forums might even blur the target site's relevance signals for Google.
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Recently there's been some talk about Google looking at links in terms of an overall "link profile". The idea is that Google has benchmarked the natural ranges for types of backlinks. So when a site begins to accumulate too many forum links (or blog links, or directory links, or reciprocals, or paid links) then any further links of that type may be either dampened or ignored for that particular domain -- even though a different domain with a different backlink profile might still benefit from an identical link.
It sounds logical, and it sort of lines up with some observations I've made. But it's more than I've tested for in any definitive way.
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The ability to do that on some forums may be missing, sometimes the signature line is generated from your profile and will change forum wide when you change it. Just like post counts.
Shortly after coming across (and posting in) this thread, I stumbled across a site providing a marketplace for buying / selling forum signature links; the first one of this nature that I've come across.
For all I know, such 'services' have been around for some time now. If not, could wide-spread awareness about this act as one more nail in the coffin for the value of forum signature links, especially at Google?
[edited by: tedster at 7:35 pm (utc) on Dec. 26, 2006]
In other words, I think you're absolutely right. Although I'm far far away from being a forum junkie, common logic leads me to believe that what you've stated above would apply to most forums, rendering any possible benefits of varied anchor text null and void.
tedster:
Thanks for moving my preceeding post here from Link Building forums. I had had a tough time deciding whether to post it here or over there, and I finally though it'd be a better fit at the other place. However, since links and Google are so closely related, I now bow to your better judgement.