If you are an SNK fan then you definitely know what Metal Slug is and respect the series either for the challenge or the graphics or both.  Well, SNK is bringing out, in Japan, Metal Slug XX for PSP. SNK has stated that MSXX is going to take full advantage of the power of the PSP system (if so, why isn't it in full 16:9 resolution?).  It will be released on December 23rd in Japan, no word on ... more.