does this mean there are some hidden unlockables as well as the featured "bonus" items???

I won the tri-nations on intensive care, but that didn't unlock anything ... so I went back to my career ... maybe if I get to the top in that something will happen, but it's taking me a hell of a long (but fun!) time.

The only listed bonus I still haven't managed is the "win with only one possession" - can't determine if the kick off counts as a possession or not - because it certainly shows in the possession stats as being your possession.