Assassin’s Creed Revelations will give the Altair story arc a real ending and will answer a lot of the questions left from the first game according to Ubisoft.

Writer Darby McDevitt told OXM in an interview;

“In order to wake up, Desmond must fix
his fragmented mind by living through key moments in history in search
of an alignment between himself, Ezio and Altar, this key moment, this nexus, is the way out of his comatose state, so
he will have to navigate his subconscious in order to escape.”

“For one, presenting the key moments of
Altair’s life as a mentor serves as a direct counterpoint to Ezio’s own
struggles with leadership. We think of Altair’s story as a small arc
within the larger arc of the main story, one which tackles many of the
same themes: leadership, family, and destiny.”

“Secondly, we are just as fond of Altair
as many of the fans are, and have always lamented the fact that his
story did not get a proper conclusion. So this is it. If you, like so
many others, are dying to know what happened to Altair when he returned
to the Apple for ‘one last look’ – as the final page of his codex states
– you will have your answers soon.”

Source: OXM