The12" has the new Red set up, Yaw FD, more quiet shifting. RBA stated it was the state if the art in 20 speeds but critizised them for not having 22 speeds.
That being said the 11" version had several issues people didn't like. A not so great FD being the main one. Loud shifting from the powerdome cassette. etc.
I certainly hope the price is going down, would love to get a grreat deal on the 12" or 13"