The PC gaming utility, Raptr, tracks the time its users spend playing titles and aggregates it into a monthly press release. Because its purpose is recording game footage, adjusting quality settings, and so forth, it is not limited to any specific catalog of games. It allows a comparison developers, publishers, and distribution platforms, as long as the average Raptr user is representative of that market.
It should be noted that, because game-hours are the recorded metric, it is not necessarily a good experiment to judge sales figures from. It is weighted by the average session length per user and how frequently the average user plays it, and not just how many people use it. As such, it will probably over-represent MMOs, MOBAs, and other multiplayer games… unless you are looking for aggregate game time, which is exactly what this survey provides (and sales figures are bad at determining).
From last month, League of Legends lost a bit of share, down from 22.54% of total to 22.25%. The second place contender, World of Warcraft, jumped from 7.63% of total game time to 8.53%. This means that League of Legends dropped from being 195% more popular than WoW to being 160% more popular. World of Warcraft is expected to jump further due to its Warlords of Draenor expansion that released in early November. The October bump, reported today, was likely due to the pre-expansion patch and promotional events.
Diablo III, the other Blizzard title on this chart, lost three places (and almost half of its play time) this month. It currently rests above Minecraft as it dropped below Smite and Counter-Strike: GO and ArcheAge moved up past it. PAYDAY 2 and FIFA 15 represented the capital letters by jumping onto the list (back onto in PAYDAY 2's case) in 14th and 15th spot, respectively.
Borderlands: The Pre-Sequel and Middle-Earth: Shadow of Mordor are new games for October, and appeared on the list in 18th and 19th place. Both titles bumped Team Fortress 2 down to 20th place, almost spiting the Halloween promotion, although its play time increased from September.