A huge win for the OpenID 2.0 single sign-on framework: Yahoo’s 250 million user IDs will now be able to log in to more than 9,000 OpenID compliant websites starting January 30. The service will initially be available as a public beta. Yahoo also announced that Plaxo and JanRain will allow Yahoo OpenID sign-ins.

Raj Patel, Yahoo Director of Membership and Registration, told TechCrunch’s Michael Arrington “This is just the first step in working with OpenID,” but Raj would not confirm when Yahoo would allow other OpenIDs to log in to Yahoo.