It looks like Ubisoft Montreal’s next IP is codenamed “Osiris”, judging from this rough cut-demo video commissioned last year. The video, posted by Vimeo user Mark Kilian, reveals that there will be a hero, a rebelling crowd, and some interesting chanting. Included is some of the concept art which has been previously leaked online, originally believed to be from a new Prince Of Persia title. Other than that, the mo-cap session does not reveal very much about the new IP at all.
Sources suggests this IP, apparently set in Egypt, is entirely new and not related to Prince Of Persia.