Comment on Google Authorship Tutorial by SEO Dave.
The question for me is how would adding 16 sitewide links (which would count as 8 links since they are duplicate sets) that pass full SEO and link benefit to Google+, Facebook, Twitter, Linkedin, Stumbleupon, YouTube, Flickr and Feedburner help Google’s users?
I’m not linking to those sites to recommend them as relevant resources to this site, they aren’t about WordPress, themes, SEO etc… I’m linking to them to promote my social media type profiles. If I added 8 sitewide links to 8 of my random domains from all 130 domains I own (millions of backlinks), I’d get my entire network banned for being a link farm!
Though I don’t think Google would penalize a site for linking to Facebook sitewide, I don’t think it adds anything useful either and it would damage this sites SEO since the links aren’t relevant to the sites content. Another way of looking at it is would Google have a problem with adding a link that’s not clickable like this one: http://www.facebook.com/david.c.law that goes to my Facebook profile?