Leaked images imply a near-future setting.
There's some morse code on the Call of Duty teaser site that says, when magically transmogrified into English, Black Ops 2.
An online advertisement for Call of Duty: Black Ops 2 has hit the net ahead of Activision's official announcement on May 1.
Is Activision gearing up for a Call of Duty: Black Ops 2 reveal in the next two weeks?
Sales of the most recent CoD are 4.2 per cent behind where Black Ops was in the same period.
FPS titles dominate Microsoft's listings for the most-played games on Xbox LIVE for 2011, with Call of Duty titles occupying the top three slots.
Activision's Call of Duty: Modern Warfare 3 sold just under two million units during its first five days on sale in the UK, according to data released by Chart Track.
Square Enix's critically lauded Deus Ex Human Revolution has topped the sales charts in the US for August. Released in the last week of the sales tracking period, the game managed to shift 244,000 units.
Activision Blizzard has reported digital revenues of $1.7 billion for the year ended June 2011, a 22 per cent increase over $1.4 billion the previous year.
The game achieved 57 per cent of sales on Xbox 360, 31 per cent on PlayStation 3 and 13 per cent on PC - although Chart Track doesn't include digital sales.
Treyarch and Activision have announced that another Call of Duty: Black Ops Double XP weekend is taking place on September 2 through to September 5. The event coincides with the first ever Call of Duty event, Call of Duty XP.