Power, stability, simplicity, and elegance

UNIX Porting Guide

For years, power users and developers have recognized the strengths of UNIX and its offshoots. While UNIX-based operating systems are indispensable to developers and power users, consumers have rarely been able to enjoy their benefits because of the perceived complexity. Instead consumers have lived with a generation of desktop computers that could only hope to achieve the strengths that UNIX-based operating systems have had from the beginning.

Interesting in that that quote essentially trashes all the pre-OS X versions. All vendors say their new stuff is the best there is, but rarely do they say their older stuff is junk.