I hope you are wrong, but yes I also feel that this could be the last year for BB Australia.
Channel 10 really should've axed it after 07 based on the ratings, but they went ahead and did another season, and we all know how well BB08 turned out.
2008 is also proof that deviating too far from the original format isn't always a good idea. Twists and shake ups can be good and as viewers we like some variety, but they can't be taken too far or else it is frustrating to watch.
Only time will tell. It all depends on the ratings really.
I guess if Channel 9 ditches it then the chance of Channel 7 picking it up would be zero to nil.
Maybe Channel 10 in their financial disarray will be prepared to take any chance. But that is mighty optimistic thinking.