Blender 3.0: EEVEE
Custom mesh attributes (generated for example by Geometry Nodes) are now accessible via the Attribute node. (03013d19d1)
Support for wavelength node has been added to EEVEE, earlier it was Cycles only. It is now similar to Blackbody node, which uses a sampled color map internally. a43c7538b8
Performance when editing huge mesh is improved. Changes in many areas are made resulting in an improvement of 2-3 times depending on the executed operation.
For a complete list of changes see T88550.