I've put this here rather than link building because I specifically mean link worth with regards to Google / PR I have noticed more and more backlinks showing from PDF's
They dont have any PR though, do the inherit the PR of the page you open the document from? Basically, the idea being if you write an article with links in and PDF it and circulate you have the potential of many backlinks - as people don't usually edit pdf's (or have the software to)....
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