I'm not sure what you have in mind, and why you think a browser based OS is an broken model. Most people simply don't need an OS in the current form. They just need something light that can run a browser and handle the hardware.
For me, it seems pretty likely that the OS will continue to diminish in importance to the point that some machines just bootup into a browser and don't have any other capability.
The advantages for users are large - no virus issues, no resource hungry desktop apps, no issues if the computer breaks/hdd fails.
I can't see why/how the OS has a long term future in desktop computing for the common man.
And from a business perspective, I don't think there's much opportunity there.
I see there being 3 computer systems people will use in the future.
The small screen / communication device (Think iPhone/Android. fine for email, facebook, communication)
The Big screen device. PVR/Set-top box/xbox/Apple TV. Consuming major media content/games/video
The workstation. This is for content creation. Writing essays. Editing Videos. Recording Music. Photoshop. etc.
Number 1 and 2 run OS's - but you don't really see them. Number 3 is the computer as we know it - but most people don't need that! I think the computer market / OS's will exist - but they will/are declining in popularity. I don't see them being taken over by webOS etc, because I don't need a computer for that - I need an iphone.
For me, it seems pretty likely that the OS will continue to diminish in importance to the point that some machines just bootup into a browser and don't have any other capability.
The advantages for users are large - no virus issues, no resource hungry desktop apps, no issues if the computer breaks/hdd fails.
I can't see why/how the OS has a long term future in desktop computing for the common man.
And from a business perspective, I don't think there's much opportunity there.