Kyle is strongly denying that he is going in the jungle but that could be a ploy but like you said I agree I don't think he would last in the jungle.
@Kaz might be right with Steve Price? Though I wouldn't be surprised if it's not him either.
Kate DeAraugo isn't exactly world famous (most Aussie's probably wouldn't even remember her) but your suggestion reminded me that Ricki-Lee Coulter and Jessica Mauboy were in the same group as her "Young Divas" and it is a possibility that it could be either of them.
David Spade is a name going around but I think he would be a little bit too high profile to go on this show. He might be a name the media puts around like they did with Melissa Joan Hart in the first season. And was it Dane Cook last year?
I agree and could imagine Jason Akermanis being the AFL legend too if it's not Dipper.
Thinking about the "singing sensation" we don't know much about that celebrity yet but Rob Mills comes to mind. I will have to check if he is doing any shows in February/March. That's my early prediction for now.
I suggested Tom Ballard for the comedian before but he has a couple of shows in February and March so that rules him out.