ok the question is simple and stated in the tittle please dont go crazy over this and start a war. i just want to know wich one looks better in terms of graphics in games like crysis 2 and mw2 and bfbc 2.
The technologies themselves don't determine the graphical quality. It depends on the game engine and models that are used. A DX11 game can look 10x better or worse than another DX11 game, and the same goes for OpenGL. It just depends on how they were utilized.
Each has it's advantage. DX tends to have slightly higher performance, but is limited to Windows. OpenGL still performs great, and is usable on numerous platforms.