[balakk]

A lot has changed since then, so why are they still so reluctant?

It's this premise that I find inaccurate. Sure there's open everything, but writing an operating system from scratch to support all this is still hard. Hell, give me one commercial operating system written from scratch in the last decade.

The point is, why do it? Maintaining an operating system is big money. And you can't stop there - you've got to have a full-stack offering - business apps, fun apps, drivers, the whole set. Add to that support, interoperability with the world, backwards compatibility etc. It's a long-term commitment; you can't back out of it that easily.

The risk-to-reward ratio is pretty small; unless you have some earth-shaking innovation up your sleeve, and/or it reinforces/supports your business model significantly.

[cubicle67]

Why from scratch? If you remove that seemingly pointless requirement then there's quite a few examples, starting with the Litl OS which is based on Ubuntu

Heck, there's plenty of good solid starting points. What about BSD? Linux? Android?

[balakk]

Still doesn't matter. Unless you create an ecosystem around your software, I think it still isn't relevant in the larger scheme of things. For eg., can Maemo, Android, WebOS etc all share applications, APIs, drivers, and other infrastructure seamlessly?

The point is you need to end up creating an ecosystem around your offering, which is non-trivial. Even if you do, you may still end up as a niche player. Litl is nice; but how well do you think they'll do against traditional netbooks?

[steveklabnik]

Depending on how you architect your OS, it doesn't have to be impossible.

I have a little Exokernel project I devote my Saturdays to, and we'll actually be able to offer a POSIX-compliant libOS, and run anything that Linux does.

Or, there's always the hypervisor route, on desktops anyway.