>This whole thing is a difficult issue. Who is to decide what devices look similar enough, to deserve calling it a “copy”?

Here's a guideline: if there is a document in your company saying ("let's copy this thing") --as in Samsung's case--, it's a copy.

Or if you created your design from leaked photos of prototypes ("as in this case") --it's a copy.

For the rest, how about a "jury" (i.e impartial to both parties common people)?