http://www.micomsoft.co.jp/XRGB-3_Preview.pdf (http://www.micomsoft.co.jp/XRGB-3_Preview.pdf)
Hopefully someone who knows Japanese can make sense of the feature list.
It's following the evolutionary path started by the X-RGB2+. It offers much higher output resolutions, but still doesn't support arcade PCBs. It has more inputs than the 2+, and a wealth of new features, but it's still the serious machine that the X-RGB2 was. Nice, but ultimately not a replacement for the X-RGB2.