I understand that Andy Diggle, announced just before NYCC by DC (and by Bleeding Cool a few weeks earlier) as taking over Action Comics with Tony Daniel after Grant Morrison leaves the comic is… also leaving the comic.
Diggle and Daniel's run on the title was already delayed by one issue as Grant Morrison and Rags Morales felt they had one last issue left in them.
Neither DC Comics, nor Andy Diggle chose to comment, as might be expected.
Interestingly, Andy Diggle has been retweeting links to Superman interviews in which he discusses issues that it seems he probably won't actually be writing now. Such as…
— DC Comics (@DCComics) March 16, 2013