Similar geometry and lights, again with Raytracing switched on.

It looks quite realistic, I think.

The next level of realism could be achieved using caustics and global illumination - Maya provides such options with the integrated Mental Ray renderer.

But the usage of caustics is a pain in the @$$, because it grossly inflates render time - it simulates the flow of photons within the scene, and it's necessary to use some hundred thousand photons to make it look good. The simulated photons of course are then bouncing all over the scene, and of course all materials and all geometry within the scene will influence their flow.

This goes until an equilibrium of lighting is reached (or until the limits as specified within the render setup are reached).

It can take hours even with very low resolution images.

I never use it.

I would like to mention that it's possible to achieve similar results with some clever lighting, using light linking.

Assume that there is a bright yellow orb next to a green one. It would then be necessary to create a yellow point light, with according fall-off, and possibly a light-linking-list to have only the nearest objects receive this light, to simulate photon flow resulting from surface-reflection.

It would take a while for setup, but the results would look very similar to the results achievable with Caustics. Light linking is still necessary in order to keep render times short(er).

Of course, when objects move within a scene, things become complicated - light-linking wise.
Maybe it would be possible to automate this using a clever MEL-script. I assume the big studios are doing this...

Anyway, in my opinion we are going to see Render-software supporting a hardware-based rendering-solution featuring caustics and globillum.

Maybe even within the next two years!