In Windows, Microsoft has the leading platform for massively multiplayer online RPGs, a breeding ground so fertile even global conqueror World Of Warcraft can't put the sleeper on dozens of rivals, from Runescape to Eve Online and on to Aion: Tower Of Eternity.
Universes, continents, cultures - so many quests and millions of adventurers, playing them religiously every day.
In Xbox Live, Microsoft has an MMO graveyard. MMOs are conceived, announced, cancelled. The pattern always seems the same. A mad rush of news stories, a year or so of guesswork, then the simmering suspicion that 'PC and Xbox 360' is, yet again, just a euphemism for 'PC and a publisher's pipedream'. Then, long after everyone's stopped listening, a single line in an interview reads: "We have no plans for an Xbox version."
So, who's the biggest fool here? Us for thinking they would happen, or them, for believing they could do it? After all, with the notable exceptions of FFXI and Phantasy Star Universe, the failure of Xbox to deliver an MMO - the type of game, you would have thought, it was born to deliver - extends back to the birth of the brand itself.
Cautionary tales of MMO disasters litter the history of the original Xbox, just as they do its successor, and what's truly remarkable is how complete a lot of these games were.
But even before Xbox, Microsoft were struggling with the MMO. After a promising start with the Asheron's Call games, its answer to the seminal Ultima Online and EverQuest, it washed its hands of the series, selling the rights to developer Turbine and focusing instead on Mythica, a rival to second-generation MMOs like Dark Age of Camelot.
Plans were also afoot to publish Vanguard: Saga Of Heroes, a hot new project from EverQuest mastermind Brad McQuaid, and True Fantasy Live Online, a hugely ambitious Xbox MMO and lynchpin of the console's Japanese line-up.
In the end, only Vanguard was released, publishing rights sold to Sony Online Entertainment. "As the development process is ongoing and constantly shifting, it became clear that (Microsoft Game Studios) and Sigil had varying visions and direction for the title's development," McQuaid explained.
Much the same was true of True Fantasy, which in a parallel universe could have changed the outlook, not just for MMOs on Xbox, but for Xbox in Japan. The star of developer Level 5 was rising, its platform loyalties split. Its dreams for the game were irresistibly huge, ranging from an evolving and reactive world to sprawling player customisation. Too huge, it appears, to survive both the studio's inexperience and a recurring theme in this story: Microsoft's stubbornness.
A key feature of Xbox Live early on was voice chat which, in an odd foreshadowing of Kinect, was touted as a headline-grabbing 'solution' to the 'problem' of keyboard control.
Level 5 struggled to implement full voice chat in the massive open world - a feature no MMO developer has successfully implemented since - but Microsoft was resolved to make it a marquee feature of True Fantasy.
Microsoft made further demands and Level 5 struggled to meet them. An ominous silence befell the project before its termination in 2004 - even though much of the game was already finished.
"The game had been showcased to the media, the world was already complete, and within it, it was possible to live a virtual life to a degree," posted Level 5 president Akihiro Hino on the company's website.