These pictures are crap. Compressed to hell and far to small to make a decent comparison. You have to play molten ruins to see the improvements. It's art direction is totally different, and the improvements are definitely there. Texture wise, U3 molten ruins wins by far. They have upped shaders and lighting as well, among other things. Which has the better art direction is to be debated, personally, I like both. But there should be no denying that the U3 rendition looks better.
Get your eyes checked. U3 MP is definitely a step above U2 MP visuals.