Maxwell Render 3.1 is out

• Full support to spotlights, fully controllable new emitters workflow. 
• Extra Sampling feature, that allows to distribute different Sampling Level values in different parts of the image, saving a huge amount of time
• OpenVDB format supported for volumetric rendering.
• 360º Animation tool in Studio, to easily create turntable and time-lapse animations in Studio in just one click.
• Camera sensor models, reproducing the color response of many real world camera models.
• White balance and Tint tone mapping controls of the render.
• Floating Shadows and Floating Reflections in FIRE.
• Support for UDIM and other tiled texture formats.
• Custom Alpha now based on materials as well.
• New Technology Preview Network System (TP Network).
• Hide to Camera in Shadow Channel, to get perfect full shadows for compositing, avoiding the 1 pixel border around the shadow without the need to launch an extra for the full shadow.
• Devignetting can not be negative, for artsy purposes.
• New output macro to specify the name of the channel in the output image file name. 

• Improved and simplified licensing procedure
• Improved Single Sided SSS model
• Improved performance in scenes with a lot of grass and/or hair
• 50% reduction of memory consumption in volumetrics
• Dramatical improvement in memory usage when loading references
• Dramatical improvement in memory usage and voxelization time in massive scenes with motion blur
• Histogram now can display RGB curves separately
• RealFlow RenderKit updated to the latest version
• Benchwell can be launched now with a command line flag: maxwell.exe -benchwell or maxwell.exe -benchwell:path to write benchwell results to disk
• Optimizations in FIRE to preprocess the scene faster when editing materials
• Fireflies and hot spots in FIRE reduced
• Added support for machines with more than 64 cores in Windows (Windows 7 or higher required)
• Cleaning after rendering in large scenes is much faster now, allows for the next frame in an animation to start quicker
• In Studio: display of references in viewport improved
• In Network: added preference to connect to a specific Manager

You can also see full release notes list.