The number of virtual world users has reached a mega-milestone this week: 1 billion registered accounts. That’s a lot of avatars. It also means a huge convergence of virtual interactions and transactions. The numbers come from the latest Kzero report, which looks at a number of metrics around virtual worlds on a quarterly basis.

For Q3, virtual world registrations were on a major boom, reaching the 1 billion mark. These accounts are spread across virtual games and environments, networks like Habbo Hotel and social networking games. And over half of these virtual users are females, age 10 to 15 years.

This demographic has had a great deal of transactional influence, particularly in industrialized eras that focus on consumer economies. Taking to online environments, there’s no doubt that marketing will further infiltrate this demographic, seeking ways in which to appeal to virtual world users.

An accompanying trend has been the development of virtual currency platforms, which will unify a great deal when it comes to virtual environments. Networks like Facebook that have already extended structured offerings of virtual currency are instilling market-wide standards for monetization and marketing to take place.

I think an interesting development in this space has been the evolution of its marketing tactics, which were once touted as breakthrough methods with billboards in Second Life, and sponsored virtual events. Instead, virtual world marketing has become a balance of user engagement and exchange, leveraging the unique environment for the type of marketing you wouldn’t otherwise be able to do. Digital products are very cheap to make but can be allocated with a great deal of assigned value, creating a circular rewards system that’s specific to virtual goods. Marketing will become both cheaper and more efficient, when it comes to scale.

Businesses looking to take advantage of this shouldn’t try to replicate offline marketing in a virtual environment. Providing value to the customer in a variety of ways will be a primary way to stand out.