Francis revealed in an interview with Emulation 64 that he will port MAME over to the GP2X as soon as the console is released:
Q : Are you currently working on any other projects besides your publicly known ones?
A : I have taken a look to a lot things, like SNES9X, DOSBOX, PCSX... But when I have started to investigate more deeply I have been 'forced' xD to continue working on my MAME GP32 port, because I have got a lot of help from people like TheGrimReaper, Reesy, Una-i, Pepe_Faruk, etc. Also with incoming GP2X appearance, I will have a lot of work to have MAME ported to the new console as soon as console appears...
The full interview can be read over at Emulation 64 here --> http://www.emulation64.com/spotlights/22/