Why there is (or might be) a Web OS

I hate to say that Tim Bray is wrong about the Cloud OS. I agree that, in general, memes with catchy titles are often meaningless when you try to explore the details. That being said, I think there are some reasonable parallels between that operating system concept (as represented by, say, Microsoft Windows, Apple's OS X and various Linux flavours) and some things available today on the Web:

• There is now an understanding that I can write software applications that will run on someone else's physical machines - whether it's via the Google/OpenSocial or Facebook way of thinking ("gadgets" portable between application "containers") or applications running on top of Web-based APIs to virtual machines like Google AppEngine or Amazon EC2. Isn't that really quite similar to the idea of writing an application to run on Windows, OS X and so on?

• It is increasingly the case that one can control these applications via relatively standardized interfaces (HTTP/XMPP/XML) Similar to the relatively standardized interfaces for writing applications in a "traditional" OS - kernel device drivers, client APIs for window manager notifications. We seem to be rapidly converging on a single UI manager - the browser.

• Specific applications may be provided by more than one vendor, and I may use various different vendors' applications integrated via "mashups". I have Google contacts, Yahoo calendar and Twitter for micro-blogging - I can use their APIs to combine their applications into a new application.

But Tim says:

The OS is the software that sits between you and the hardware. In practice, it offers a set of brutally stupid and complex services for managing storage and networking and the lowest level of user interaction. It’s difficult and unpleasant to use.

As defined by Windows et al, that might be true. But isn't it possible to improve on that concept by providing services at a higher level (my location service, my contacts service, my "lifestream" service)? Wouldn't it be nice it we could use those services from more than one vendor? Don't we need a bit more standardization than AtomPub? What if there already were a standard?

Note that I do NOT think that there is a Web OS - I think we should avoid calling "it" that, anyway.

But what if if we could define and make a "Cloud OS" that is related to the traditional kind (roughly as noted above) but demonstrably better than any machine-based one - would the meme be more useful then, Tim?