Remember how the multiplayer characters in the last Assassin's Creed were kinda random? Well, in Revelations, they'll be a bigger part of the game's story.
Ubisoft's been making a serious effort to implement new features/improvements in each of the Assassin's Creed games. In Assassin's Creed: Brotherhood the big new feature was a multiplayer mode; that the characters that were available to players were sort of random, largely coming from small side quests. However, the next game will feature multiplayer characters who are more involved with the single-player storyline.
A recent Game Informer story details the major characters that will appear in Assassin's Creed: Revelations. This includes details on some of the multiplayer characters, all of whom sound pretty interesting (FYI- the Guardian is pictured here):
The Vanguard is a Cossack from Odessa. She joined the military to help hold the Ottoman Empire off from her homeland. Eventually, the Templars recruited her with promises of money and power. After years as a scout and spy, she is striking more directly at the center of the Ottoman empire.
This intriguing character is the estranged cousin of the first Sultan of the Sennar Sultanate. He was driven from his home in 1505 by his own family, and ended up in Alexandria, where he began to encounter the Templar philosophy. He now calls himself the Guardian of Truth, as he aims to enact the Templar mantra of peace through order and stability.
The Bombardier is part of the Ottoman artillery corps, but that isn't where his true loyalties lie. He is actually a member of the Quizilbash, a group of anti-Ottoman rebels. The Bombardier thinks that working for the military is beneath him - a weakness exploited by the Templars, who use him to get weapons and information in exchange for wealth and access to powerful men.
The Sentinel's similarity to the garb of an Assassin isn't coincidental. He was once part of the Assassin order. Born a Wallachian noble, he joined up with the Assassins as a teenager. He stayed with them until the Assassins established a truce with the Ottomans. Enraged, the Sentinel betrayed and left the order to join the Templars. The Ottomans had invaded and conquered his lands - a sin the Sentinel could not forgive. He now uses his insider knowledge of the Assassins to bring down both his former compatriots and their Ottoman allies.
The article also includes a lot of information about the characters that appear in the single-player campaign. It'll be interesting to see if, aside from expanded backstories for these multiplayer characters, the multiplayer mode includes other new features.