Arnold has been updated to 7.2.5, and Maxtoa to 5.6.6.0
The new things in Arnold are a much faster rendertimes and time to first pixel, both using gpu and cpu. This was possible thanks to rewrite most of the code to Nvidia optix 8. And a reduction in ram used while rendering both in cpu and gpu.
Global light sampling is now available in volumes,
Distance shader is now visible in reflections and refractions:
A new overlay mode allows to add any text over the renders:
Improvements on denoisers in cpu and gpu. And an important one: In arnold renderview, the ability to select objects directly clicking in the image was only available on interactive rendering, but now is available also in production mode after the render is done.
You can see all the new features, here.