There is a general discussion going on about the name of this very popular OS - ie whether it is OK to call it just Linux or should it be addressed as GNU/Linux.
My view is that the GNU movement has made major contributions in bringing this Operating System (OS) to its present popularity. An OS is as good as the tools that are supported by it. And a majority of the tools and softwares in linux are licenced under GPL (GNU Public Licence). Think of what would have happened if Linus Torvalds had released linux kernel under a propritery licence - Would it have seen the light of Day? It is only because of the CopyLeft GPL licence that it has become so popular without it being hijacked by any million dollar corporation.
But you are free to call this OS *Linux* or *GNU/Linux* as long as you acknowledge the role played by the GNU movement and realise that the term *linux* only denotes the kernel which is the heart of an OS but it is now commonly used to (wrongly) denote the OS as well as the programs that are bundled with it.
Also it is my belief that each person who is putting this OS to productive use should address this OS as GNU/Linux (especially infront of laymen and newbies) so that they come to know the real facts and the GNU movement is not overshadowed in this process.