Check the last couple
peeks of the week, and other previews in the
Announcements forum. The latest peek is on music, but the one before it was on the Crystal Bag (can contain up to 5 magic crystals to provide bonuses for the person carrying it). I don't recall any previews going into much more detail than that.
Several recent previews have described a little bit about summoning dolls (the specific example was boosting the doll's resistance to a certain elemental attack, and giving it an elemental attack effective against the creature it needed the resistance for). Once summoned, for a limited time, they become controllable just like you own characters, and you can use your own skill points to boost their abilities, if you wish.