All technical arguments aside, I call it GNU/Linux because rms politely asks me to.
"Over time, calling the system GNU/Linux spreads awareness of the ideals of freedom for
which we developed the GNU system. It is also useful as a reminder for people in our community
who know about these ideals, in a world where much of discussion of free software takes a
totally practical approach. When we ask you to call the system GNU/Linux, we do so because
awareness of GNU slowly but surely brings with it awareness of the free software ideals of
freedom and community."
I think it's a valid request, and to me it's not overly cumbersome. Granted, at first it feels
a bit strange in a conversation where the other parties are using "linux", but then again, the
system being "strange" and "unorthodox" is what got me to run it in the first place.