I hate how all the big players (Yahoo, Microsoft, Google) are implementing the OpenID provider half of OpenID, but refuse to be consumers of OpenIDs from other providers. It really defeats the purpose of OpenID. I'd even call it arrogant. Though I suppose it's better than a completely proprietary system like Facebook Connect.

It's painfully obvious they just want to remain in complete control, while reaping some of the benefits of OpenID. I'm really hoping this will backfire on all of them, and OpenID becomes hugely popular to the point where users demand they become real OpenID consumers. It's going to take awhile though.