Janrain has announced end of service for myOpenID, one of the many OpenID providers. MyOpenID will not be available starting February 1, 2014. (An earlier Twitter announcement from Janrain hinted at the same but did not set a date for end of service.)
This decision was made by Janrain, and Stack Exchange did not have any part in it.
You can still use myOpenID to log in to Stack Exchange, but be aware that any outages in the myOpenID service will mean that you are unable to log in to Stack Exchange until Janrain fixes it – which may take several days, or weeks, or never. After February 1, you will no longer be able to use myOpenID to log in to Stack Exchange. Stack Exchange will not be able to answer any questions about why myOpenID is down or when it will be working again. If you do not have any other login credentials on your account by February 1, you will be locked out, and Stack Exchange will be unlikely to help you recover your account.
To avoid getting locked out of your Stack Exchange account, we strongly suggest that anyone using myOpenID as their primary (or even backup) login add a new login method to their Stack Exchange account.
We're also going to remove the "myOpenID" button from the sign-up/login page soon, in order to discourage new users from signing up using myOpenID.
Here's how to add a new login to your account. You must be logged into your account when you begin. (This information is also available in the Help Center.)
Open up your user profile page (by clicking on your login name at the top of the screen) and click the "my logins" link above the bio box on the right hand side.
You should see a list of all of your logins.
To add a new login, click "add more logins..." at the bottom of the box. Choose the new login from the list and follow the steps to confirm.
If you choose, you can remove your myOpenID login by clicking the same "my logins" link, then clicking "remove" next to myOpenID.
If you are adding a Stack Exchange OpenID, you will receive a confirmation email. You must click the link in the email to confirm your email address before the Stack Exchange OpenID will show up under "my logins". Please make sure that you are already logged into your account when you click the confirmation link; otherwise, you will create a new account that needs to be merged with your old one.
If you encounter any trouble adding logins, or accidentally create a separate account that you would like merged, please fill out our contact form.