I was watching gamespot's live stream so I could watch some games. I was watching the guy playing Sports Champions, when I noticed he was using two Move controllers. Does anyone know if you can sub out one of the move's for the navagator, or do you need two moves, or just one?

You don't need two moves to play sports champions.

I was gonna ask the same question, archery you need two controllers?

You can use two moves if you want to, it will give you added control, but it isn't required.
 
From the PS3 press release for the game:

 Further immerse yourself into the action with an optional dual wield control to aim your bow, use your sword and shield, or set up that perfect spike with both hands.

Gladiator is much better with to move controllers. 
Archary as well.