Realm population limits

We don't have any technical limit at all - they can be as large as needed.

Because the gameplay takes place in instances, it's very easy to add more servers to handle load as the game grows.

The town you saw is our Act 1 town, which is the smallest of the towns. The towns do have player limits, so multiple instances of the same town are spawned. The town player limits vary based on the physical size of the town. You're generally placed in a town instance that has more of your friends or guild members.