There will be some big changes to rendering with the new version of Maya, which will no longer ship with mental ray but Arnold as the default rendering engine. This follows the Autodesk aquisition of Solid Angle, the creators of Arnold, earlier this year.
NVIDIA will continue mental ray as its own product and is releasing a free beta version for Maya 2017.
The native edition of Arnold can render a single frame or a sequence of frames, but batch rendering is not available and images will appear with a watermark. To remove this you will need to buy separate Arnold batch rendering nodes.
The new version of Maya also extends the new Render Setup System, that was introduced in Maya 2016 extension 2. It replaces the legacy render layers system in Maya and can be used with third party renderers. The update includes a feature for rendering a sequence of frames without the need to batch render. Watch the Render Setup introduction video below to get the basics of the new system.
Other news added to Maya 2017 is the Time Editor, a new non-linear animation tool which lets you switch between keyframe and clip-based detail, and a new Bifrost Ocean Simulation System (BOSS).