He was recently interviewed in Cannes and gave a passing mention to his upcoming project: "It is a very light comedy that I am filming now, a court drama, based on a video game, the Nintendo game DS."
Akward translation aside, Ace Attorney seems to fit the bill.
His filmography already included a video game adaptation with Like a Dragon (a.k.a. Yakuza on western shores), which was perhaps closer to what moviegoers expect of Miike, best known for violent movies such as Ichi the Killer and Audition.
If anything, we can at least expect a faithful adaptation.