From what I have seen Samsung's 10nm is about 10% denser than Intels 14nm.
The whole nm thing is mostly marketing albeit usually at least some parts do have a "feature size" of that size specified. All sorts of factors like number of fins, fin height, fin pitch, gate length, etc come in to play.
Then of course the manufacturing part is only one piece of the puzzle, the chip design also will impact logic densities since this is also a Samsung chip on the Samsung manufacturing process its worth noting. You know if AMD's old bulldozer chips were made on Intels 14nm they wouldn't all the sudden be Kaby Lake's.