You said it was turn-based - doesn't that kill the immediacy of combat?
In single-player mode there are two different turn methods; the familiar 'you take a turn, then wait while the computer has a go' and the simultaneous turn mode. In this mode the computer makes his turn while you're making yours, making it a semi-real-time mode. In combat, too, you can choose to use either a fast combat mode in which battles are resolved automatically and immediately, or go for the traditional turn-based method.

Presumably you'll be able to use allied units in combat?
Allies will automatically be drawn into battle if they're in a hex that's next to a battle that you're involved in, and no, they get their own turn and fight for themselves.

What happens in multiplayer?
Now you're dealing with a more traditional battle scenario without the unfolding storyline stuff. Up to 12 players can join in through a LAN or via the Internet. Again, there are two turn modes available so everyone's catered for.

Sounds like it could be giggle.
The Dutch developers, Triumph Studios, have put a lot of store in the racial interaction that happens in the game, and if they manage to deliver what they promise, Age Of Wonders could well turn out to be a nice addition to the genre. We're certainly looking forward to playing it.

With mine large staff I shall turn thee into a toad and squash thee underfoot!
Twit. Hop off.