WordPress.org single sign on has been fixed for most of the various sections. Themes still needs an upgrade, and the codex plugin needs to be modified for the new cookie structure, but most of the main bits are working now.

For you moderators, this change will very likely have invalidated your admin area cookies. So if you find you can’t access an admin screen that you should be able to access, log out then log back in before trying anything else. This should only be required once, to get the cookies to reset themselves to the correct names.