Maya 2017 Update 3 - UV editor changes/improvements

You'll first notice the lack of the mult level icon bar from the top of the UV editor, and that the tools have all migrated into the new UV ToolKit. 
I think the best bet is going to be to take the tools you like,and put them on the new UV editor shelf .. unless you are a fan of the toolKit style of controls. 

I'm digging the new Color By Shell option to show the different shells, and while I still prefer to select my edges, and then cut UVs, having the cut UV tool work interactively in 3D space is a very nice addition.

Senior Techincal Specialist Steven Roselle takes us through some of the new UV tools and UV ToolKit in this video






full list of update 3 improvements

http://help.autodesk.com/view/MAYAUL/2017/ENU/?guid=GUID-2197CC8C-4D8B-412D-9073-47F0E877BAEA