It seems that Google has finally gone on the record that longer domain name registration has no impact on your search engine rankings, at least not at Google. A Google Webmaster Help thread has a post from Googler, JohnMu, who said outright that it doesn’t make sense for Google to use this as a ranking metric.

Let me quote John:

I think that is pretty convincing that Google doesn’t use the domain expire date as a metric.

What is funny is that we discussed this topic a few times in the past. Each time, we never really came to a conclusion. But it didn’t stop domain registrars from using this as a marketing tactic.

Forum discussion at Google Webmaster Help.