[George W. Bush]

Are you talking about general tasks, or specific software it doesn't run, like Exchange? And since it's BSD, what does Linux do that it can't?

I was thinking particularly about studies done on using it in production web server farms. Tiger Server, while fine for smaller intranets and such and coming stock with Apache and all the usual web server stuff, simply doesn't scale well compared to the excellent Linux offerings. Even Windows Server does much better at load-balancing and other tasks in production environments. You just wouldn't run Amazon or Google on Tiger Server.

OTOH, Apple has some nice stuff for Grid, a service that lets you create server farms easily to do stuff like rendering. And they have really good stuff for connecting, say, a dozen computers each with a half-dozen external and soft synthesizers together via networking and MIDI to create an integrated professional music studio. They have stuff to share devices like CD/DVD burners to all the machines on the network.

So Mac has a few advantages, more in the arts and scientific area, that PCs don't quite match. But Windows and Linux servers in heavy networking or webserving environments are not going to be replaced by Tiger Server. Still, Tiger Server works fine for small to medium intranets so it's not useless, just not designed or intended to take on the server market.

[antiRepublicrat]

Even Windows Server does much better at load-balancing and other tasks in production environments.

I have to disagree with that. I've used Windows NLB in production, and it sucked badly. Anyone doing large-scale NLB should be doing hardware NLB in the first place.