I don't see what people have against exergaming. Plenty of people find DDR (and its clones) to be a fun activity, plus they lose weight doing it. Just like any other sport. (Fun fact, DDR is a registered sport in Norway)
Likewise, plenty of people find interactive workout programs like Yourself!Fitness, Gold's Gym Cardio Workout, EA Sports Active, and Wii Fit to be a fun and engaging way to workout. Just like exercise books, DVDs, CDs, or gym memberships are to other people.
There is no magic pay-x-amount-and-you-will-be-healthy solution. I could spend all the money in the world on gym memberships, personal trainers, p90x, and whatever else the 'serious' exercise afficienados say is clearly superior, but it does me no good if I never use it. The same goes for Wii Fit, DDR, a treadmill, or even just getting a good pair of shoes and going for walks. However, there are clearly some things that are more likely to draw people back for more.
For example, when I played DDR, I found myself going back to it not for exercise, but simply because it was fun. I only stopped when I got tired of the tracklist; and I still fully intend to get a PC mat and plug it in to stepmania eventually. Likewise, lots of people probably keep in shape by playing football (both NA and soccer), basketball, or swimming-- not because they do it for exercise, but because they do it for fun.
Likewise, I've recently taken to taking walks around town, especially in the early morning. The various sights and sounds are much more interesting on foot than in a car, plus it gives me time to listen to audiobooks, language tapes, and the like. It also allows me to get around nearly free; the only costs being my time and a bit of extra wear and tear on my shoes.
The same things might not work for someone else, though-- I know people with little sense of rhythm, and they do horribly at DDR. If they tried it as a workout regimine, they would quickly fail. Likewise, someone living in a city that doesn't enjoy wide sidewalks and clear skies might find walking around to be an unpleasant experience. What matters is finding something that works for you, and who cares if that's a set of DVDs and books, a video game, or a personal trainer and gym membership if it works?
As far as weight loss is concerned, for the people that are obese or overweight, and really need to lose weight, anything is going to be an improvement over doing nothing, the important thing is sticking with it. Just an office worker replacing their trip to their cube on the 5th floor two or three times a day with taking the stairs would be improving their health. Now, if you're talking about getting a great form, awesome muscles, and very strong for someone who is already in pretty shape, yes, they're probably going to need some harder, more complex stuff. But there's a big difference between those that want to lose weight and those that already have a good body shape and want to improve it.