As I have stated time and again, many of us now live on the Internet as well as the real world -- meaning, it is real to us. Thus, following any political, ethnic, or religious tensions, an online aftermath follows.
Defining what cyberwar means is not easy, but one thing I know for sure: Attacks by hacktivists or people trying to make their voices heard (if in an illegal fashion) do not make warfare.
To date, I believe two attacks qualify as computer attacks-based information warfare: