This is not a canonicalization attack, although it is similar. The attacks described used semantically different strings that just happened to look like what the user was expecting.
I believe it's called a "homograph attack", or at least that's one name for it. Wikipedia has an article on the internationalized-domain-name version of the attack, and the various attempts by registrars and browsers to mitigate it: http://en.wikipedia.org/wiki/IDN_homograph_attack
On the same page. You can call them "Homograph Spoofing Attacks"