The XGP and GP2X are two different consoles by different companies. The XGP is mainly geared towards 3D commercial games. It is rumoured that it is possible to run homebrew on it. Check: http://gamepark.com/
The GP2X which is the console in the picture currently has two commercial games lined up for the summer and has an excellent homebrew developer base at the moment. Check out this review for more details: http://craig.gp2x.de/review/GP2XReview.html
As for the whole GP2X vs PSP debate in terms of homebrew, both have disadvantages and advantages. For example the GP2X has Mame 0.34 and NeoGeo MVS/AES running at full speed with sound (with some overclocking) but lacks in the Snes department.
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