The image on the left is a sphere sticking
out of a flat plain.
For each of the four textures shown,
I computed an expression using noise,
and evaluated it on the plane so you could
see what the texture looks like.
Then I took the same texture,
added some color table and lighting stuff,
and evaluated it on the surface of the sphere.
It is clear from this composite image that 3D lighting and color remapping add a lot, and are very effective in completing the look of noise-based textures.
There is a natural progression in the examples on the left, and in the next few slides we'll be going through them one at a time. It's best to read the image starting at the top-left (just noise) and going counter-clockwise, ending at the top right marble image. In each successive image the expression using noise is made a little fancier, and the resulting look changes.