ken_b - 4:21 am on Mar 10, 2010 (gmt 0)

Allow siteowners to log into G Webmaster Tools > list all backlinks > check a box next to each link that should be discounted > confirm

That might work for a new site, but if a site already has thousands of backlinks, going through the list to approve/disapprovem them would probably be unmanageable.
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