These days, just about every game released features an online multiplayer option and many of the most popular titles in the world only achieved that lofty position due to that multiplayer action.
One could argue that Microsoft and Halo most inspired the multiplayer explosion on consoles, and selecting other revolutionary titles from other publishers would be a relatively simple endeavor. But Activision's bread and butter franchises – Call of Duty , Guitar Hero , and World of Warcraft – only rule(d) the world because of multiplayer. Granted, the latter is on PC and that platform has been utilizing MMOs for great profit since the late '90s, but the point is that Activision appears to understand the nature of the industry. They know that considering the global scope of the industry today, if they can get everyone to play together, they'll make billions. And so they have.
On the downside, many have called out CoD for having short campaigns and, in a sense, those who only play single-player (or don't care much for multiplayer) feel short-changed with each new installment. Guitar Hero was entertaining for a while when playing solo but let's face it; that name became synonymous with "party" fun. Call of Duty wasn't the massive blockbuster it was until Modern Warfare , when that game started to climb the multiplayer popularity charts. After supplanting mainstays like Halo and Gears of War , there was no looking back. This makes one wonder: Activision is the biggest publisher in the world. They're well aware of how they got there.
So is Activision most responsible for this multiplayer boom? Of course there are dozens of other factors but considering the sheer popularity of their multiplayer-oriented franchises, and the meteoric rise of their company, one has to consider the possibility that a single fast-rising publisher pushed multiplayer farther than anyone.