A cyber Pearl Harbor did not happen. Stuxnet and its kin did not take out any power grids or shut down cities. Mobile threats continued to escalate and malware became more sophisticated, but none were as game-changing in nature as Stuxnet was. While there were still plenty of data breaches, including a handful of big ones, they were much smaller in scope compared to the TJX and Heartland breaches of a few years ago.
Even so, several security related events in 2012 could well be harbingers of things to come in 2013.