The sold-out xxxHOLiC x SOUND THEATRE stage event has updated their website with a lovely CLAMP illustration and new information. This event takes place 1/28-1/29. It stars the original anime voice actors and live music.
Also there is a CCS-themed Line app for your phone. I'm not sure if it's available outside of Japan, but the link sends you to an English-based website. If anyone tries it, please comment. :)