> What current bat book does the best Joker stories? Why?

Paul Dini's Joker in Detective is the best current version IMHO. As for why, he has a great take on the Joker, as a completely mercurial, utterly warped lunatic, who can chat pleasantly with you one moment, commit insanely evil acts the next, and genuinely not understand the difference between the two, or worse yet DOES understand the difference, and just doesn't care.

The All Star Joker does nothing for me, and the Confidential arc requires one to accept that Bruce Wayne would arrange to have someone killed.