Gruber speculates that Windows 8 Metro-only ARM tablets would make for terrific iPad rivals, and that there’s no reason for Windows 8 ARM to run “desktop apps”. It would be an interesting bet that would make sense in many ways; there’s the chance for a clear start, finally.
Here’s why it’s not going to be that way.
The build-up to Windows 8 has focused on marketing a definition of “no compromises” that involves being all things to all people in a way that desktops, laptops and tablets all get both environments. Microsoft has set the expectation that Windows 8 will be both the desktop and Metro and that Windows 8 ARM hardware will be no better or worse than x64-architecture hardware. Windows 8 ARM is supposed to be able to do all that Windows 8 Intel can. Microsoft is interested in offering up old and new on both the “old” platform and the “new” platform and they see it as being beyond a feature but a necessity.
Microsoft’s position on the environment duality is that the desktop half won’t even be loaded until you use it initially. Metro apps run in a new environment with more rapacious process and power management and may not unto itself mean doom for battery usage. With this in mind, Microsoft gets the chance to tout the only alternative that remains fully a tablet OS as long as you only do tablety things and that can be talked into running Office when the need arises.
It’s not just that it makes sense through Microsoft’s constantly backwards-compatible-colored glasses, but that it makes a lot of sober business sense as well. It’s a trite example, but surely the enterprise that’s currently and somewhat shockingly the iPad’s biggest supporters wouldn’t mind an alternative that could also run Office and their old libraries and Windows programs? Office isn’t available for ARM right now, but probably will be within months of launching. Programs and libraries can mostly be recompiled and work for ARM; something like Excel is shock-full of hand-written assembly routines. Given the ramifications, there’s no reason why porting this isn’t the Office team’s highest priority from now until Windows 8 ships — split with starting the Metro versions, of course, but that’s done by complementary teams.
Windows 8, even with both environments, can still be used to power an iPad rival. I certainly didn’t expect to be writing that until just recently, but it’s true. Microsoft has made the right bet and made it look like the recumbent “let’s do nothing and hope we still win” position. Windows 8′s tablet chops are now on the non-ridiculous end of the scale and you could do something brilliant with Metro apps. As long as the market is seeded with lots of Metro apps, there won’t be very many reasons to run desktop apps. In such a situation, Windows 8 tablets will be able to compete based on the apps that will be running and not foiled by the power management tax of the desktop code that could be running.