Yup! It just hasn't hit the custom layouts yet, and that's one reason why a lot of people aren't panicing. Though, I have discovered that you can still use subject lines in the reply via email forms, so there's that. I don't know when that's being phased out.

Did you import it, or was it manual? And if you did import it and it futzed with something, you can file a service/support ticket so they can fix it so it won't happen to anyone else in the future.