North Korea, bombastic, crude, dissembling and enraging it may be but it's leadership is not stupid. They know that George W. Bush would like to settle the issue of their nuclear program but if they wait a year, George W. Bush may no longer be President.
N. Korea has two options, it can rush into an agreement with President Bush if they think he will give them a better deal or, if they think a President Kerry would serve their interests better, they can keep the door open to negotiations while ensuring that nothing much happens until the new administration opens for business in January, 2005.
There are no circumstances which Kerry can directly influence the direction of negotiations and there are no circumstances where it would pay for Bush to delay a success in negotiations past the elections. Thus, the US side is very predictable in its actions. The only thing that will vary is North Korean behavior based on North Korean political evaluation of the two potential US presidents from 2005-2009. North Korea's evaluation of who would be worse for their repressive dictatorial regime will be crystal clear. So far, it seems the dictators prefer President Kerry.
Update:
The Financial Times is playing this same 'kremlinology' style game of observing the North Korean's preferences and has an article observing that John Kerry is getting very good press in N. Korea.