There an experimental build for windows that has the ability to import 3dm file into Blender Nubrs surface object but is at early stage and need some workaround after importing.. now file import can read rhino 6 or higher file.
This at early stage and need some tweaking of surfaces with end point U V. And for now don't supports all features, such as trimmed surfaces but works better after saving file and open that in standard build e changing the end point selecting sometime both end UV or one side end..
Below my test.












Link to Blenderartis topic.

https://blenderartists.org/t/branch-soc-2014-nurbs-update-to-master/1207889/6