Activision says that it shipped US$1 billion worth of Call of Duty: Ghosts copies to retail for its first day on sale.

This figure may seem to trump the launch of Grand Theft Auto V last month, which achieved US$800 million in sales on its first day. But there's a key difference: Activision’s figure is for stock shipped to retailers, while Rockstar’s figure is for games actually sold to consumers.

Prior to the launch of Grand Theft Auto V, last year's Call of Duty: Black Ops II was previously the fastest-selling game of all time, selling US$500 million at launch and taking 15 days to reach US$1 billion in sales.

Although Activision stopped short of providing sales figures for Ghosts, the volume of units purchased by stores gives some indication of how quickly the game is likely to sell. More than 15,000 stores around the world opened at midnight for the launch of Ghosts, Activision claims.

"Ghosts is an amazing game which ushers in the next generation of Call of Duty," enthused Eric Hirshberg, CEO of Activision Publishing.

"This is the must have launch title for the next generation of consoles, and we expect Call of Duty: Ghosts to be the most successful launch title for the Xbox One and PS4 by a wide margin. In fact, according to GameStop, Call of Duty: Ghosts is their most pre-reserved next gen title."

It’s notable that the $1b figure for Call of Duty: Ghosts includes Xbox 360, PlayStation 3, Windows PC, Wii U, Xbox One, and PlayStation 4 copies – even though the next-generation platforms are not yet released. Grand Theft Auto V is only available on Xbox 360 and PlayStation 3.

Even if sales of Call of Duty: Ghosts do not outpace Grand Theft Auto V, it will likely be the more profitable game as it was produced on a significantly shorter development cycle and at a lower cost.