Previously, when players were caught cheating, they were given a warning and had a temporary ban for three days, that was up until the most recent 1.3 patch.
According to the official forums in addition to a number of tweaks and optimizations, a number of anti-cheating improvements have been implemented. “All cheaters detected by the system will be banned permanently”.
Ubisoft has been pretty hush-hush about their actual “anti-cheat” methods, which is probably for the best. The more information that potential hackers have on these game mechanics, the easier it would be to potentially exploit them.
Of course, there will be a number of players out there that will complain of being falsely accused of cheating and will be banned, that goes without saying.
For more info on the 1.3 update and Ubisoft’s anti-cheating measures, check out their AMA on reddit.