The former Neighbours actress and Rogue Traders singer, who also presented reality TV show So You Think You Can Dance, will now join Ronan Keating, Guy Sebastian and Mel B on the panel for the Australian version of the television talent contest.
Bassingthwaighte told Who magazine that she had a hunch that "2011 would be fantastic", especially as "11 is [her] lucky number".
The star was first linked to the show in March, when presenter Luke Jacobz said that he had heard her name mentioned among producers.
Mel B was confirmed as a judge last month and later said that she thought the experience would be "fun and very interesting".
Former judge Kyle Sandilands announced earlier this year that he would not be returning to the series because it involves too much "work".
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