From IGN Hands-on
On the 360, PC, and PS3 the Overlord's minion cap is 50. Here on the Wii, because of less processing power, that cap is currently at 25. The developers are tweaking the game to see if they can't raise that number a tad.
The early level we played took us through familiar obstacles, if you've played Overlord. Gameplay could be described as evil Pikmin. Your minions will dispose of enemies, flip switches for you, and move boulders out of the way. While some adversaries have been reused, like the beetles, new ninja-like bad guys are also present. We encountered a pretty impressive golem boss that was three times as tall as the Overlord. Our minions overpowered it, and the creature fell backwards into a pit, creating a bridge to reach the next area. Nice.