You can also see the new lighting effects. Note that the cobblestone closest to the camera is normally white, but as the room is lighted by torches (which give off orange light) and there is no alternative form of light (e.g. Moon-->Violet or Sun-->White) the blocks at least 3 blocks away from it that still receive its light are lighted with a tannish-orange tint, hence the cobble stone near the torch being White (original color) yet those surrounding it being orangish-tan. You can also see on the right the water filtering the orange light into blue light.
The purple light you can see on some blocks either comes from the moon (if this is exposed to moonlight as moonlight gives off violet light--seen in another 1.8 photo) or the water is filtering the light from the torch to be purple/blue---which can also be seen in another ravine picture