I guess it wasn't a let's-distract-everyone-from-Breaking-Dawn leak after all...
If I tried to write Midnight Sun now, in my current frame of mind, James would probably win and all the Cullens would die, which wouldn't dovetail too well with the original story. In any case, I feel too sad about what has happened to continue working on Midnight Sun, and so it is on hold indefinitely.
She's posted the partial draft as well. The link is at the end of her note about the leak.
Nope. Still haven't read it.