So the GOA add new account button suddenly didn’t work after I upgraded to Gnome 3.10.
I note this fix but it doesn’t work for me. https://bbs.archlinux.org/viewtopic.php?id=170965
I’ve been looking long and hard for a fix for this. I will update as soon as I find it.
Update: Solved it.
pacman -S gvfs-goa
I filed a bug report, seems this is now a dependency.