|Is Google Authorship officially dead?|
For now.. Yes.
However for those of us working on clients.. Google Publisher Tags (GPT) are very much still alive.
Which means Schema is still important.
And if Schema is still important than Authorship just got moved into Knowledge Graph and KBO (Knowledge Base Optimization), based on Schema. It would dictate.. "that the "Entity" related to "Author" is a "Person within an Organization" .