One point you have missed though is GPL does not mean "FREE"
as in "No cost"
The was nothing stoppng anyone from selling Linux Distros in the past ,Linus is just trying to protect His trademark.
One thing that needs to stop for Linux to continue is the absolute mad number of Distros being created often from different development streams
And with IBM and others already using Linux , Microsoft Linux# is a real possibility ,they have done the same thing before, (C# ,Jscript, Vbasic ) are just 3 of many examples of Microsoft embracing existing technology and Making Money from it.