On the eve of MacOS X's release in March 2001, after I had been beta testing the product for six months or so, I predicted that one day, the visual effects and animation companies that I worked for would be using Mac OS X.
Six years later, it hasn't worked out that way.
I thought this was a pretty safe prediction because most of these companies were originally formed using SGI boxes, coding with C and OpenGL. SGI peaked in 1997, and when it became abundantly clear circa 1999 that we were going to have to find a new platform altogether, most ditching SGI started pondering Linux. First it started in the farm. This actually started at a company I worked for in 1995. By 1998, Linux renderfarm machines started rolling in by the truckload. Then when SGI started its death spiral, the desktop was tackled. Linux support from nVidia with OpenGL drivers came out around that time. One day we got this Gee - Force card from them with some beta Linux drivers to try porting some of our custom software to Linux. The rest is history.
Well, not quite. Getting there was a long, hard road. The port of tools took a long time, and lots of IT things had to be worked out. One of my former employers had to fly out the kid who wrote the NFS code in Linux to help out with problems. And today, Linux is still a pretty poor platform when it comes to production (except the farm). No native Photoshop. Actually, not many commercial digital production tools of any kind. Productivity tools are completely absent, so producers and coordinators still can't be on the same platform as the production team.
MacOS X seems to be a great direction for 3D production currently on Linux. It has all of the tools artists need (i.e. Photoshop), even project managers can use it for their tasks, and it's shell-friendly and OpenGL.
Apple even tried to force this issue by purchasing the only two major compositing tools available for Linux and Windows (Shake and RAYZ) in 2002. They subsequently killed the Windows version and, while the Linux version is still supported, it costs 10x what the Mac version costs.
It will be interesting to see what large production companies do in the future. I'm guessing they'll stick with Linux. They all have good deals on hardware with PC vendors anyway. Newer shops are all opening up on Windows and the old guard will probably stay with what they've got... leaving MacOS back where it was originally... in the editorial suite.