you mention the Commnity in your headline and ODOO in your text.

I'd say the best way of "Certification" from the Community would be to propose it for any of the existing OCA repositories. If it is accepted ... that's like a certificate in a way. I guess for many people who are insecure which of the many many Community Modules out there to trust the fact something is issued under the OCA umbrella is worth quite a bit.