Fans line up for Call of Duty: Modern Warfare 3

[caption id="attachment_296" align="alignnone" width="650" caption="Enthusiasts waiting to buy the lastest version of Call of Duty at a Melbourne EB Games outlet."][/caption]

THOUSANDS of gamers have declared war and stormed the shops for the latest instalment of computer game Call of Duty.

Sales are tipped to rake in more than $1 billion in just a few weeks.

Gaming stores at shopping centres including Tea Tree Plaza, West Lakes and Munno Para opened their doors at midnight, as part of a co-ordinated global launch for Modern Warfare 3.

The game's "campaign" mode continues the saga of global warfare and intrigue developed in the first two instalments.

Players must stop an invasion of North America and Europe by a Russian enemy force, while the narrative brings to a close the story of "Soap" and "Price", the two Special Forces troopers who've been the heroes of the series.

But the biggest drawcard for most gamers is the multiplayer mode, where teams and individuals playing on Xboxes, PlayStations and PCs across the world battle it out in real-time to earn points and rewards.

Retailer EB Games said the demand had already eclipsed any other title in the company's 14-year history.

The Call Of Duty franchise's past two releases each grossed more than $1 billion worldwide, putting them in the ranks of the top-earning entertainment titles in history, across music, film and gaming. More than 30 million people played Call Of Duty titles online in the past year, with an average 6.5 million people logging in to play on any given day, distributor Activision said.

Ethan Blaine, assistant manager of The Pimp Pad Adelaide, a video games bar on Franklin St, said the game's accessibility and ease of play was a major contributor to its success.

"It's such a popular game because it is so easy and fast to play," Mr Blaine said.

"Because you can go in with all guns blazing and it's not about teamwork, a lot of people really like that aspect of the game."

RMIT University new media expert Dr John Lenarcic said games such as Modern Warfare 3 were popular partly because they made action heroes of everyday gamers.

"We're talking about photo-realism that approaches or surpasses cinematic quality and people can actually be embedded inside that narrative," he said.

A promotional video featuring Australian actor Sam Worthington and an AC/DC soundtrack has had more than two million hits since it was posted on YouTube on Friday.