I have written up rules for starting Reiatsu but I haven't quite materialized it yet. I know what I want and how it's going to done, to a certain degree. I'll try to write up more over the weekend.
On another note, have you guys seen the most recent chapter?(#345) I'm going to say a little of what happens in the following spoiler text.
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Ulquiorra has released his zanpakuto. He says, "Bind, Murus-Hierago" and a whole lot of crazy goes down. In short, Ichigo is screwed and read the chapter already!!!!