Jesus fuck. What about it? The engine is old, and the game looks like shit. But Obsidian fixed the Super Mutants, reintroduced some of the classical weapons, armors and enemies, and made the world look a lot more believable. Hell, they even added little details like a crow flying away from your grave when you visit the Goodsprings Cementery for the first time. Ceasar's Legion looks distinctive enough, so does the NCR. The strip looks nice, especially at night, with all its neon lights lighting the area. The architecture is spot on, and every casino has its own distinctive look and feel. Super Mutants and Geckos move exactly like they did in FO2.
It's a post-apocalyptic world on a dated engine. It's not supposed to look pretty, but it looks believable, and that's what matters most. What did you expect? Lush forests and golden rye fields?