I would say that it will likely pop up on the Japanese sites in the next week. And then possibly within the next two weeks on Western sites.
Once Tamashii shows the "official shots", much like these with the Japanese text and displaying the accessories, pre-order time soon follows.
One thing they didn't show is what multiple hands he will come with. There's obviously a fisted set, and also one to hold the grapple-gun with. I hope he has some open pairs and one to grip the Batarang with. I wish he came with more than one Batarang....