GNOME
=Ubuntu Desktop Edition
KDE
=Kubuntu Desktop Edition
Unity
=Ubuntu Netbook Edition
(Lucid/Maverick+) &Ubuntu Light
UNR
=Ubuntu Netbook Remix
(<=Karmic)Plasma-netbook
=Kubuntu Netbook Remix
Foundations
= kernels/X11/toolchain/linaroServer
= redirect to serverfault.com ? Unless it's about byobu or setting up deb mirrors/proxiesbranding
= "How do I get back to [x|k|studio]ubuntu wallpaper/login screen/plymouth"
The idea is that "Ubuntu Desktop" question will most likely be about GNOME/GUI apps & desktop environment. Similarly "Kubuntu" question would want an answer for KDE/Qt apps. Similarly netbook-remix'y should only deal with those customised UI's instead of general app questions.