Yahoo! is jumping on the OpenID wagon and is making it possible to use your Yahoo! account as a valid OpenID. That’s another quarter of a billion OpenIDs out there! Put that together with the fact that AOL made their AIM logins work as OpenIDs as well and most everyone in the US at least will already have an OpenID.
At 37signals, we love OpenID. We support it in Basecamp, Highrise, and Backpack and have integrated all these applications through OpenID with our OpenBar. Our users seem to love it too. One in ten Highrise users is running with OpenID.
It seems the Yahoo! system is still under development, though. And it does require that systems accept OpenID 2.0, which is the only just-minted new standard (what everyone else in the first rush just implemented was 1.1). So we’ll be making sure that our systems will be ready for OpenID 2.0 and all the new Yahoo!-wielding OpenID users coming on board.
Rock on, OpenID!