I agree with everyone so far that almost nobody is going to pay and go through the hassle to download Mega Drive games from a specific site when there are a ton of other handhelds that let you do it for free from any ROM site. HOWEVER, according to this
A developer can either:
a) Make direct use of the standard linux kernel framebuffer for sound and the also standard ALSA kernel subsystem for sound.
b) Use the SDL (+SDL_gfx, +SDL_image, +SDL_mixer, +SDL_net, +SDL_sound, +SDL_ttf) to program graphics and sound.
c) Use DirectFB for graphics (included but mostly untested).
Obviously the preferred choice is (b), since the included SDL has been tweaked and optimized to work with the specifics of the machine.
The developer can make use of any of the other included libraries (for example for reading XML configuration files). If he needs a library not included as standard, he can just compile it and distribute as part of his application (in the same directory).
Developers are welcome to suggest libraries to be included in our firmware.
Porting an application that ALREADY runs on linux should be quite easy, given that it is suited to the 320x240 resolution. In some cases the developer will just have to tweak the compile scripts or make files to use the GameGadget toolchain compiler instead of the host system compiler.
Porting an existing linux application can be sometimes very easy, but I don' believe anything can run "as is" without some work." Taken from this official page http://www.gamegadget.net/developers/info_14.html
I am no expert, but it seems that if this were all true, people could play homebrew emus without having to pay for roms as long as some one stepped up to the plate and ported emulators over to the console. If this were possible, I think that the GameGadget would be a lot more reasonable. H.G.