Exactly how much it matters I can't say. But I can say that it does matter. Why? Because for one thing a whois record with valid info is cached in various pl

Exactly how much it matters I can't say. But I can say that it does matter. Why? Because for one thing a whois record with valid info is cached in various places and creates unique info which is repackaged on other websites that get slurped. Next, we run a whois server for our registrar and it does get hit by google bot every single day. Along the same lines the registrar you use for your domain also matters. None of this means that you can't rank well with private registration. But unless you've got a specific reason to have privacy on your records there is no question that it is an advantage (for seo and other reasons) to have your info public (not to mention if it's private you stand a greater chance of losing your domain name..)