Rovio, the company behind the hit game Angry Birds, has confirmed a Christmas themed version is heading our way, following a recent Halloween special edition.

On Saturday, Rovio confirmed on Twitter the new festive version would be available: "Any day now." Angry Birds Christmas will be offered as a "free update" to existing users and not sold as a separate app.

The company is also expected to release Angry Birds on Windows 7 mobile devices in the New Year.

Meanwhile for Angry Birds fans, the first official Angry Birds day has been announced.

Saturday 11 December, 2010 will hopefully see Angry Birds meet-ups around the world via

"In one year, Angry Birds has become a global phenomenon. Different versions of the game have been downloaded to smartphones and tablets over 36 million times. People everywhere spend their bus trips, train rides, rainy days or other idle time playing Angry Birds, talking about Angry Birds, or creating fun stuff around Angry Birds," Rovio notes on a blog post.

"We thought that it would be a fantastic idea to join up with other Angry Birds fans and have even more fun! The Rovio Team will host an event at Elisa Studio in Helsinki, Finland, where we will webcast interviews and chats with our developers, fans and friends."