From 1.6 Trello page, they have to finish:
DR - Testing and debugging
DR - DR on slaves only, without workstation
SPEED - Automatic AA/GI multiplier
BUG - Terminator problem
BUG - Slow interactive renderer
MEMORY - Geometry optimization
UI - Collapsible categories in tonemapping tab in VFB
UI - Layered Mtl UI improvement
SCATTER - Scattering on splines
SCATTER - Regular patterns