I think the next major movement in grouping is going to have to be separate knees and elbows. shoulders and butts can often be hidden under clothing, but elbows tend to stick out at unfortunate angles. If you look at the "superposeable action figures", some of them have 2 hinging points at knees and elbows to allow for better posing. There actually IS a separate knee bone in us humans. ;) Carolly