Some people think that for Linux free software under a copyleft license (which forces you to release every changes under the same license) is only one option of many. But it really isn't. Why is that? Because there is really more a choice of if hard- and software development follows the Linux/ free software path, what would mean that Linux at some point gets the support it deserves, or it will not. If still many hardware vednors release closed source drivers and many companies rather release proprietary software on Linuzx and do not give back code, Linux will suffer in that sense that it can not compete with Microsoft and Windows. This is because the progress and the development model of Linux are built to use free software rules. Where companies and users are leaving these road the progress gets halted. So the real "war" is not "WIndows" or "Linux" but it is a clash of software cultures where Linux must convince a critical mass to follow the freedom rules. if it will not Linux will fall back to something "just better as Windows" that will be a bit more open but will not help to get the freedom that would be needed for Linux to provide all functionality to be competitively successful against Windows Vista.
So many people falsely think that a bit of a progress should be enough and that if some more people just use Linux that this would be benefitial and should make us happy. It should not! In an interesting interview with one of the Samba developers I have heard that until today Apple Computer which built the code on FreeBSD has not given one cent of money back to the further development of FreeBSD. So the BSD licensing scheme is mainly helping big companies and Linux would be have the same problems if it would not have the GPL for its protection.
It is often seen as dogmatic if one takes this kind of position, but this is not a position of the pure teaching but rather it is about what is essential of Linux and how we can preserve or extend what was once the successful motto.And many big companies like IBM already see this. The thing is that these GPL rules also encourage companies to share not evene because they must, but because they know that everybody has to do this, so they know the code they give never can be occupied (or stolen) like this once happened to WINE.
So the purpose of this post is to encourage to act in the sense of the GPL and to not forget what made Linux so powerful.