Actually, at Be we love Linux. We use some Linux (and FreeBSD) systems as file and network servers interconnecting our BeOS systems, Windows systems, and even Mac OS systems.
But this points out a basic difference -- the two operating systems are designed to address two different sets of problems. Linux, FreeBDS, and Unix in general are terrific server operating systems. They make great mail, file, and web servers, and can perform many other network management tasks. Linux and the other Unix variants are more directly comparable (and compete with) Windows NT.
The BeOS was designed from the ground up to allow realtime manipulation of streaming digital media, like digital audio and video, on consumer-class hardware. It's a very different emphasis, and the BeOS does it very well -- better than any other operating system, we believe.
So, Linux and other Unix flavors are great for certain tasks, while the BeOS is terrific at other tasks. You probably have room for both on the same network, and indeed, the two of them compliment each other extremely well.