Nick Bonner's view is correct (and I know him personally). Nick did receive a calendar and he loved it.
For the first time Americans were allowed to travel with Europeans and we had more freedom. The "guides" are more guides than guards. It always scares me that we will get some arrogant person that we all have to watch. The guides have asked me to help. I may photograph but I am not going to run off.
Treat the guides well and you will be rewarded with a "special stop" or improptu visit. If you are respectful the guides pick up on that. Asking polite questions pays big. This is Asia and rules of conduct apply.
It can be an amusing game because there are two sets of rules. On Mount Paektu there is the rule "Do not take photos of soldiers." However, we are allowed to hike around so I follow a group of women soldiers and watch them. After a short time I take a photo and they love it. Soon I am having a great time with them. My roommate comes by and reminds me of the rule. Then he realizes they want their photo taken. We go to work. This is Korea and there are the rules then there is reality.

So the rules can change depending on the location. You have to be careful but judge the situation. Let someone else shoot a photo to see how the guides react. Subtlety is also helpful. Hold the camera at the waist and shoot there. A small handheld in the palm works great for crowds. It is surprising how the Koreans have grown used to cameras.
It will be interesting to see how the tourist industry is this year. The Cheonan incident did not affect tourism at all and I wondering how the shelling of Yeongpyong island will affect numbers. I predict it will not.
One of the most fascinating thing about going on these tours is to meet people as crazy as yourself. You do make long term friends on the tours. Just think, who else would really do this sort of thing? You meet people like myself who have been to the "more difficult" places or the dark tourism types. I have been to the wars and the revolutions and I must say that the DPRK is more like a "vacation" than the Yugoslav war was. We have a nice bed, a good view and a bus. People are much more nice in Korea. There is not much danger of the food being bad than some I have had in other places.
Check out the offerings at Koryo Tours and Asia One on One. Not cheap but you get some time in China which to me is more like a coming home. My long term plan is to move to China at some point. That is another society full of discovery and new places.
A co-worker has a friend who is an FBI field agent and she told him that her boss went to North Korea annually. He told her that could not be true and she was mixing up North and South. She emailed him the above photo. He still is scratching his head.
When I went the first time and posted photos in 2008 at least three people emailed me and asked me where I had stolen the photos because it was impossible that as an American I could go to the DPRK. I would send them the information on Koryo and a photo of myself there. One person said it was photoshopped. It is amusing but annoying. That does not seem to happen much today. My point is to get as much in-country time as possible. Right now I have 21 days and I will add 16 days this year. I am going to keep going until I really have seen and experienced what I can. The Tumen Triangle tour Koryo offers sounds interesting to do also.
On a budget? The November winter tour is cheap and the airfare to Beijing is very cheap at that time.
Ray