Re: SUPER UBER SPOILERMANIA: The Ending... What Does It Mean?
Or they are continuing suspense by saying he's dead rather than immediately admit he's locked away somewhere? Either way, Hopkins would be back anyway as he would have play Odin (even if it's Loki impersonating him). And, I thought at D23, he and Portman were do exciting and anxious to do a third. (I'll try to find the quote).
Hopkins would have to come back as I doubt Thor would have no idea about Loki taking over Asgard just because he's on Earth with Jane, so Loki would need to continue the Odin charade. Thors not exiled like the first film and promised to protect the Nine Realms, so I'm sure Heimdal is zipping him all around by Thor 3, even if his home base is now Earth.