Plan 9 is not the most elegant design of OSes, but its simple ways of combing primitives are pretty amazing. Simplicity is underappreciated nowadays.
Would you mind saying why? It isn't unstable or anything, just unfamiliar, in that you can't write C programs on it. But people do use it in production.
With inferno they went the VM route (the dis VM) and built it so that it runs on myriad platforms, from Unix and ActiveX. It still runs on hardware though. The intension was that you can run a network of hosted and native inferno installations, making it easier to adopt. Unfortunately, inferno saw no widespread adoption either.
The underlying filesystem concept is basically the same (the latest version of 9p and Styx are identical), but the programming environment changed a lot (you write limbo to run on dis). Also the user space programs were rewritten and get overhauled a bit. The community never get divergent enough though; inferno people tend to identify themselves as part of the plan 9 community.
be sure to click to the repository, it has an overview of the 26 steps (so far) to get to the point where it is now.
also congrats to the author for getting to this stage, with steady improvements.
I have high hopes for this, though, since Inferno is a lot of fun to tinker with.
http://plan9.bell-labs.com/sources/contrib/miller/9pi.img.gzRhetorical question is rhetorical.