GmenuNX is just a opk that is provided with the v1.6 update but 2x is still the default UI and they can switch from both with one click personally i prefer 2X because its simple.
Hi! I like Gmenu2x but i want try GmenuNX, the RG Gmenu2x (And the zero version i supose) was a fork of the ben-nanonote Gmenu2x (Mantained by qi-hardware), and this one also was a fork of the original Gp2X Gmenu2X...
Then we have the next:
GP2X Gmenu2X (ARM SOC)
Gp2x Wiz Gmenu2x (ARM SOC)
Ben nanonote Gmenu2x (Ingenic soc but not opendingux, distro based in openwrt)
And those versions just in 2010!
Somekind of "change" seems fresh for me actually, im feeling like i have a pcmasterrace running win98 :-)
But is just my opinion :-)
Thanks for the new firm version :-)