What happens if a user wishes to transfer his social status > an account?
1) Changing the password is easy from the UCP, as you would normally do. The only thing lacking at the moment is a warning of some sort to tell the user that if he doesn't have a password set (because (s)he registered with a social account AND Flyover's passwordless option is active, so no password was set upon registering), he doesn't have to fill in the "Current password" field. You can easily add it though to your theme's usercp_password template.
2) Users are required to specify an email anyway upon registering. The emailless feature has been removed from 2.0, so now every user who registers with a social network does have an associated email which can be used to get new credentials using the standard MyBB's password recovery form.
2) Users are required to specify an email anyway upon registering. The emailless feature has been removed from 2.0, so now every user who registers with a social network does have an associated email which can be used to get new credentials using the standard MyBB's password recovery form.