Less than a week after Facebook’s BlackBerry app got better BBM support, Research in Motion (RIM) has announced that its flagship instant messaging service, BlackBerry Messenger (BBM), now has voice calls enabled within the app.

BBM Voice was first announced last month as a feature available to beta users, but BBM 7 should be rolling out in BlackBerry App World any time now. It will require BlackBerry 6 OS and higher, though support is planned for smartphones running the BlackBerry 5 OS some time early next year.

BlackBerry’s instant messaging service has proved a hit with countless people around the world, particularly with teenagers who use it as an alternative to text-messaging, as it’s free to use with other BBM users.

Now, with the latest version of BBM, you will be able to easily switch between a standard text-based message and a BBM voice call, which will be free to use over a WiFi connection.

In addition to this, BBM will also now notify you when there are new updates to the app from within the app itself, while BBID Synchronization means your BBM Profile, Groups and Contacts are now linked to your BlackBerry ID.

With RIM’s updated Facebook app launch last week, the latest incarnation brought in a slew of new features, a new look-and-feel and, crucially, enhanced BlackBerry Messenger (BBM) connectivity. This meant that users could now discover and add BBM friends, as well as initiate chats, directly from the Facebook app.

As for this new voice call feature, well, it’s an interesting move for sure but the WiFi-only stipulation will likely hinder uptake, especially when you consider other cross-platform alternatives such as Skype or even Viber. Free 3G calls would be a much bigger deal than it is at present, but it’s certainly a notable ‘pivot’ for what is one of RIM’s core applications.

Meanwhile, you can see the first official BBM Voice call for yourself in the video below. And remember, the app may take up to a day from now to appear in your local App World store.

BBM | BlackBerry