I was under the impression that Swedes and Norwegians (maybe others?) can understand each other's spoken languages fairly well, but to easily read another Nordic variant is a different story.
*cough* ... depends. To me, Norwegian<->Swedish is mutually intelligible when spoken, quite a bit worse when written. Norwegian<->Danish is the other way round, to the point where I have deep trouble conversing with Danes but few misunderstandings in writing.
And Icelandic is pretty much as obscure as Latin. We catch a fascinating old-fashioned word here and there, but the gist of things mostly escapes us.
