Back in July, Valve boss Gabe Newell cracked open the floodgates of Windows 8 criticism, just ever so slightly, when he said Microsoft's new operating system, launching today, would prove to be a "catastrophe for everyone in the PC space." Then you heard the echoes of other high-profile PC game backers, who vocalized their concerns about Windows 8, such as Blizzard's Rob Pardo and Minecraft creator Marcus "notch" Persson. "Stop trying to ruin the PC as an open platform," Persson told Microsoft, directly. But aside from the random tweet or shallow game dev vox pop, few people (if any at all) really publicly broke down concerns surrounding Windows 8, until 17-year video game industry veteran programmer Casey Muratori did his due diligence and really put Windows 8's policies under the microscope. A self-professed "grumpy old man," he criticized those policies for their lean toward a closed platform controlled by Microsoft. For him, individual Windows policy choices raised major red flags, but he found something much more worrisome than simple, yet potentially pernicious, policy changes. "I look at it from a more holistic standpoint," Muratori tells me from his home base in Seattle. "What's happening right now with Apple, and with what Microsoft is about to do, very clearly represents a shift in the power structure of how software is developed. It's not just a policy change; it's not just another 'thing.'" He continues, "There's an underlying mindset, and that mindset is a feudalistic mindset -- there is a plantation that a company will set up and own, and developers will work there, and they will pay whatever the tithing or tribute is, and developers have to pay that." If you haven't been keeping up, here's the primary concern with Windows 8: This new OS sports a new "Metro" UI, which is now just referred to simply as the "Windows 8 UI." If a game developer -- or any developer -- wants their product to be compatible with all the fancy new UI features that Windows 8 offers, that software must be subject to Microsoft's policies, certified by Microsoft, and sold through the official Windows Store. But that's not a problem, right? Developers will still be able to make and sell games via the older desktop interface -- the open interface -- many have argued. "To some degree, I think that [argument] is almost immediately obviated by two things," says Muratori. "First, with Windows RT, there's no desktop on Windows RT. On one entire SKU that Microsoft is shipping, that [argument] is not relevant, because RT is not shipping with a desktop. So everything that ships on that platform goes through Microsoft. "Microsoft didn't say [RT] is only going on phones. For all you know, the next set of desktops could be ARM-based processors. The next set of ultrabooks could be Windows RT. A whole slice of the Windows-based market could be Windows RT. There's nothing stopping that from happening." Secondly, he adds that with the "proper" non-RT version of Windows 8, apps made for the old desktop cannot integrate with any of the new features offered by the OS. "What ships on Friday, all the new stuff, is off limits to you, if you don't play by Microsoft's rules. You can't ship a game with [Windows 8 features such as] Share if you don't ship through their app store and pay the toll."

A concerned PC game industry

When top people from places like Valve speak out against Windows 8, they're not just talking about restrictions on releasing their games, but about their own distribution services. If the desktop interface is marginalized or -- theoretically -- eliminated, under the current policies, Steam would not be allowed on Windows' new interface, or sold through the Windows Store. Why? Because the new UI's certification requirements prohibit "Metro"-style apps from downloading executable content. That alone is a clear explanation of the whole "catastrophe" remark from Newell, and one can imagine that other digital storefront owners feel the exact same way. While people like Muratori are skeptical, Microsoft has tried to assure gamers and developers that it won't mess with the desktop side. "We want the world of desktop apps to to keep existing [outside of the Windows Store]," Windows Corporate VP of Web Services Antoine Leblond recently told Gizmodo. "There's no reason to get in the way of that. Valve can keep being Valve." Statements like that do little to allay concerns. PC game developers and executives have been quiet, even diplomatic about the changes Windows 8 will make. But rest assured, we know from highly-reliable sources that decision-makers in the game industry are extremely wary of the new OS. They just don't want to come forward about it quite yet. These are what we hear are the most common concerns from the game development community:

Apple envy

Matt Ployhar works at Intel's Visual Computing Software Division where one of his focuses is on games. On the side, he's head of the PC Gaming Alliance, a group of companies with a vested interest in the advancement of the PC as a game platform. Previously, he was on the Windows 7 and DirectX planning teams at Microsoft, so he knows a thing or two about the company's ubiquitous OS. A through-and-through PC game advocate, Ployhar admits that when he was at Microsoft, he decried the idea of the Xbox, and wanted the company to instead focus on making Windows a better platform for games. He's standoffish about saying anything specific about Windows 8 at this point, but as someone who played an integral role in planning Windows 7, he couldn't help but opine. "Microsoft's smartest thing to do would be to move heaven and earth to work more closely with their OEMs in order to be more competitive with Apple," he says. "Some people might say they have done this and are competitive, but then look at Apple’s trajectory over the past decade. The uncertainty we're seeing by developers that's being covered in the press surrounding things like Windows 8 UI (Style/Metro), and Surface RT, make one think, 'Oh God...Please remove some of that ambiguity.'" The success of Apple has shown how dominant a "managed experience" can become, says Ployhar. Apple platforms strike a managed balance, in that it has some of the advantages of an open platform, and some of the advantages of a closed one. That doesn't mean that Microsoft should adopt the same tack with Windows. "[Microsoft] ought to replace the perception they've created in having Apple envy," he says. "They just have to stop that. I don't advise chasing Apple's taillights. They need to change the game, stop getting into the mud. Apple has so much critical mass right now, I'm concerned that a lot of people are going to get steamrolled by it."

The Ultimate OS

So we know the reasons why many PC game developers are wary of Windows 8, but if Windows 8 is so bad, what's the ideal -- the ultimate -- PC game OS? Well, there's the open-source Linux, a platform that Valve's Newell said could be an option for game developers if this whole Windows 8 thing doesn't pan out. Steam now supports Linux, and Newell said games can be key to platform adoption. Muratori argues that Linux just isn't stable enough, and it would take a concerted effort by big developers to make Linux a truly viable option. Who knows -- maybe Valve would spearhead such an initiative. But before the situation would become so dire that game developers shun Windows, surely Microsoft would listen? What happened to "developers, developers, developers"? Ployhar says Microsoft could overturn some of the more restrictive policies, down the line. "This would play into one of Microsoft’s biggest core strengths, and what helped make them so successful and ubiquitous in the first place, which is to keep restrictions for developers to a minimum," he says. (Microsoft recently said it will fix a policy issue that would have restricted M-rated games from the Windows Store, for example.) Muratori says that Microsoft does have a history of sometimes listening, and sometimes not listening, to developers. But even if Microsoft does hear pushback from the game development community, and even if it wanted to change, the new UI and app store are so much a part of the new OS's foundation and fundamental strategy, it'd be extremely difficult to roll back the moves, Muratori argues. "Something like this is a real bottom-line issue." As for the "ultimate" PC game OS -- maybe that is exactly what the industry is beginning to lose with Windows 8. "It's pretty clear that this was the best market -- an open market with a stable OS, that was actively supported by commercial companies, seems to be the best thing we've had," says Muratori. "Windows 'pre-this' was it. We were looking at the best thing that we had."