Just a heads up, the final volume of the Geass manga has been released -
It has quite a few differences that you are able to read and see here :
http://community.livejournal.com/cod...s/1666465.html
(you have to be a registered member)
In case you are not a member there, I can at least copy/paste a few differences that were noted. ( full credit goes to leizelann from LiveJournal. )