The original posting was a bare announcement in comp.os.plan9 for people who were already familiar with Plan 9. The newer article adds references to some introductory Plan 9 documentation which would be very helpful to someone new to the OS.
An advantage of going native rather than VM, especially with an OS as small and simple as Plan 9, is that you can have complete control and understanding of what's running on your machine - no mystery processes you didn't start, no little webservers opening ports behind your back...