Apart from the skinny "Advanced MS joint", there is going to be another layer of parts on top of it that form the inner frame. Also, looks like you can choose between the Core Fighter (transformable I believe) and Core Block for the body unit.
And movable fingers just like the MG version as seen in image 2 and 3 as well. The color separation for the parts is going to be pretty amazing as well. ^^
July 24th release, 2,625 Yen (inclusive of tax).
Images are from Amiami.