Frank I don't know if you follow Q but if you did you know it was all settled in November when they met the first time but the media was not told. This now is all theater for the media.
Martin, that is how these things usually happen. The two leaders don't have the extensive knowledge and background to actually negotiate. They set the parameters and prepare the stage in public, so the REAL work can take place behind the scenes. This is truly a remarkable time, and the opportunity to finally end the Korean War. Perhaps there will follow a second summit that includes South Korea, Japan, North Korea, China and the U.S.