If I want to persue some black hat tactics, how important is it to have unique Whois information with your registrar? I'm already planning every site to be on a unique C-class IP, and won't use Analytics or Webmaster tools to link sites together. Do I still need to bother using unique contact/admin info at my domain registrar? Or won't Google be looking at that? And if it does matter, does using an anonymous registrant help or will that just be a bad signal? And if it should be unique, then how unique (name/mail/address/phone)?