In spite of all this mess, Batman Begins was greenlighted with Christopher Nolan attached and the suits stayed the F out of the way. How this happened totally escapes me, but thank GAWD it did. Then, last year, Singer was immediately attached to Superman when the McG deal fell through a second time. That giant "woosh" you heard was the fanboys sighing in relief.
Side note: I should point out that di Bonaventura was responsible for getting the Matrix sequels, T3, Oceans Eleven and the Harry Potter franchise under WB's umbrella, so the man should have been cut a little slack for Pluto Nash. The director of that pile of s#!t is the one and only soul who should have been held accountable. Just like Schumaker has been persona non grata in Hollywood ever since B&R. Then again, "Ron Underwood" ain't a household name, now is it?
Anyway, Horn has said that he does want to do BvS, but only after both franchises have been rebooted. You continue to hear little bits here and there from the current participants in both projects. I can only say this: Don't let Wolfgang Peterson touch this project. If Superman doesn't suck, and if BvS does get the green light after a new trilogy in each franchise, then the ultimate fanboy wet dream will be a co-director gig from Singer AND Nolan. I haven't even heard that mentioned.
To answer the question about why it's called "versus" ... yes, you heard that right, and you are reading the word right. The premise as I understand it is that Bruce Wayne's fiance is killed, pushing him totally over to the "dark side" of his vigilantic nature. Superman steps in to try and redeem his erstwhile crime-fighting friend. I didn't read the leaked script ('cause I don't like those types of spoilers) but that's the gist. Batman and Superman do indeed go at it for the sake of Batman's soul. And it does make sense that if you can rebuild both franchises, then get all of the players on board for a joint operation, you'll have the greatest star-studded action film since The Dirty Dozen AND you'll be invested enough in the characters (because you've invested in the actors portraying them) that you'll give a crap. Again, if they can build a real character out of Rachel Dawes, as they seem to be doing, then she can become the catalyst for this incredible turn of events. Have the balls to kill her off at the end of "Batman Begins a Third Time" and she'd be the Gwen Stacy we were denied in Spider-Man. It'd be the cliffhanger that "On Her Majesty's Secret Service" was meant to be, setting up a monumental fourth picture.
If I ran WB, these scripts would already be hammered out, all the stars would have been signed to a four-picture deal (for each franchise, the fourth being the joint picture), and the directors would have personal stake in making damn sure they didn't screw up the franchise along the way. You'd get seven back-to-back blockbusters guaranteed.