Hi I've been finding some places to post backlinks and have used Yahoo site explorer to see where else someone was linking from. This one guy is a member of a load of forums and he's posted multiple adverts with backlinks in every single topic area. Thousands of them. I think he's the only person posting there. Do all of these backlinks count? I've heard a lot of people say no, only one per domain but this guy has gone crazy with it and his site is highly ranked in Google. I suppose there must be some value in them, even if they carry less weight than if they were on different domains. The PR for the domain is 7. Is it worth me spamming a load of backlinks myself?