The use of the 'comment' feature on someone's status update on facebook to conduct a personal conversation, unrelated to the status.
Pam: "Oh look! I have like 20 new notifications!"
*clicks on notifications only to realise that she has been status hijacked once again!*
Pam: "Oh no, it was just Adam and Ayden pulling yet another status hijack. Oooooh those boys!" *shakes fist*