I see the same behavior. If I drag in a material node and connect it to the current model, Octane crashes. It's possible that it's due to my model being big (almost 1GB) and the update creating a delay, I guess.
If instead, I drag in the material, click on it to see what it looks like, and then while the material ball is visible connect it to my (invisible) model, Octane doesn't seem to crash. When I go back to my model, the new material is visible correctly, on the model.
I'm not sure if this is true for all materials yet: I'll do some experiments when I get some time.
Mac Pro 3,1 / Lion / 14G RAM / ATI HD 2600 / nVidia GTX 470
i5-750 / Windows 7 Pro 64bit / 8G RAM / Quadro FX 580
Revit 2011, SketchUp 8, Rhino