Game signings

The Burning Crusade is the first big expansion of the massively multi-player online role-playing game since its launch in 2004.

Initially it was due to be available at the end of 2006 but Blizzard delayed the release saying it needed extra time to "polish the game".

Illustrating how revered the game is by its followers, the development team behind The Burning Crusade will be signing copies at four Californian stores when the game goes on sale at midnight on Tuesday. Shops across Europe will also open so fans can get their copies early.

In anticipation of the expansion, Blizzard has released a content patch which will set gamers up for the expansion.

Continued dominance

Since its launch, World of Warcraft has easily become the most popular online role-playing game.

The game puts players in the fantasy world of Azeroth and they can choose to control a range of characters and professions. World of Warcraft now has more than 7.5m players around the world.

They can carry out quests and go on adventures, where the killing of monsters is rewarded with either money or more powerful equipment.

A preview of the expansion, shown to the BBC News website, suggests gamers will not be disappointed by the updates. Improvements are likely to see it maintain its dominance of online adventure gaming.

Players will be able to buy The Burning Crusade from retail stores but so far there are no plans to let people download it.