The basic game is pretty basic: you hack and slash your way through countless faceless hordes of warriors, wielding the wiimote as a sword or as a spear. There's some variety in the weapons you use (bow, gun, cannon, boomerang, sword, spear, hammer, yoyo's (!)), and each has its own special moves.
There are 'officers', who are slightly tougher than the regular troops, but the game really shines when you're up against a 'main' character -- they have loads of weird abilities and attacks, and you just have to try to take 'em down with your a spear and a gun!
There is some variety in activities as well: sometimes you have to race a horse, sometimes you have to pick a lock, sometimes you have to run to get somewhere while dodging traps... Sometimes you're on 'rails', other times you can choose which way to turn, and still other times you're in a free-roaming level.
The game is not very hard once you get the hang of it, and the missions are reasonably short as well. Perfect for a non-hardcore gamer like me who wants to play a game with lots of (motion-)action.
There's a 'versus'-mode as well as 'trials', but I haven't really played those.
I don't think it would be worth the EUR 60 you're paying in shops here, but for the EUR 40 I paid for it over at Play.com, it's certainly a good buy.
And we 'finished' Super Mario Galaxy, that we had on loan from xaviar_nl and gertvr. Really great 3D game with a clever idea for physics. Some levels are devillishly hard. The two-player mode (where the second player is the 'co-star' that can hold enemies or harvest star bits) makes it a great spectator game too.