Knowing that TD5 is almost here, here are some of my predictions on what MIGHT happen in Season 5:
1. Duncan will not be one of the Top 3 members of his team, just like in the first three seasons.
2. If Duncan gets eliminated before Heather, then she'll maintain her "Highest-Ranking Contestant" status, because she made it Really (x3) far without returning (i.e. Semi-finals in TDI and TDWT, and almost made the merge in TDA, meaning that she was eliminated an episode before the Gaffers and Grips merged).
3. Duncan will suffer the same fate that Heather (TDI), Justin (TDA), Courtney (TDA), Alejandro (TDWT), and Scott (TDRI) went through. In fact, when we saw him fall to his death in TDWT ("Walk Like an Egyptian - Part 2"), people thought Duncan had a Disney-esque Death, because (in real life) falling off a plane, without a parachute, can cause a very serious injury. However, his punishment didn't last long, as he was caught in "I See London...".
4. A girl will finally win in Canada. In fact, I think Season 5's Final Two will consists of girls. As for the Final Three, a pattern in which a big bad (Heather/Courtney/Alejandro/Lightning), a tough (Gwen/Duncan/Heather/Zoey), and a goofy (Owen/Beth/Cody/Cameron) will continue.
5. Gwen will make it farther than she did in Action and World Tour.
6. Cameron might end up as the Highest-Ranking Member of his team, again.