A few weeks late, but I just got my copy today.
I really liked the arc, and I hope Vaughan stays on longer.
I'd personally like to believe, that Apokalips was nothing more than a voice in Sinister's head, and I'll take it as exactely that until he is revealed as something else. Problem is, though:
The final scene is so tempting, that future writers might give in to the temptation of bringing apocalypse back, even if Vaughan had done it only as a teaser.
I'm still waiting for the voice in blockbuster to be explained, though.