Page 1: "They say all things of this world are impermanent," the Sensei possibly predicts Batman's departure from his own title, but at the very least forecasts his own demise at the end of the issue
Page 2: As far as I know, the Sensei's Men of Death are a new entry to the Bat mythos. Like Damian's foes in 666, I'd swear Morrison slapped these guys together from super villain color forms
Page 2: Rama Kushna, patron goddess of Nanda Parbat, transformed Boston Brand into the superhero Deadman. In 52 (in what I'm positive is a Morrison scene), Diana Prince expiated her murder of Maxwell Lord before Rama Kushna, who absolved her of the crime.
Page 4: Hmmm, tough choice Ra's. I know you really need a new body, and I feel just awful about it - breaks my heart - but you should take Damian. What? There's a third option so that nobody needs to be sacrificed? No Ra's, you can't take any chances, it's too dangerous. Go the safe route and take Damian's body, although I will surely be sorrowed by losing him.
Page 12: "My son," another instance of occupational inheritance, which we saw with Damian in 666 and Cyril the Knight. Who will inherit the mantle of the Bat? Find out in Battle for the Cowl, coming this March!
Page 12: "You and your witless daughters" - The 's' belongs, believe it or not. Ra's Al Ghul sired a daughter before Talia, the now 250 year old Nyssa Raatko, who obviously enjoys a good dip in the Lazarus Pits every now and again (unlike Talia). The by-all-accounts excellent Death and the Maidens by Greg Rucka expands Nyssa's backstory.
Page 21: Ra's now wears a monk's skin, yet another instance of possession.