There are those that think that technology will somehow allow us to keep wasting energy, and undoubtedly to some degree it will.   As conservative people, we don't see the point of risking it, when easy and fairly cheap alternatives exist, which in the case of keeping your home warm, they certainly do.

You don't go out in the winter in a bathing suit, yet we think nothing of putting skimpy amounts of insulation in our houses, simply because the industry hates change and it might cost them some short term profit.  In our view, even  the current requirement of getting energy-star certified isn't nearly high enough.  We say stuff insulation everywhere until most of your heat loss is due to windows and air infiltration; beyond that its a waste.  If for some reason, that's not practical, just do the best you can.

Dual pane windows are still terrible insulators, and currently (2005) very few manufactures make a "high" performance triple glaze window, all of them are in Canada (you can find them on www.energystar.gov: you're looking for one with a U value of .2  which is R5).  Ask for them, because until people do, no one will build them.  There is in depth information on the subject in the tutorial under heat loss and issue about types and placement of windows in solar, as well as some additional considerations about windows in design.

Air infiltration is a tougher problem, because you need fresh air.  What you don't need is drafts, and what you'd like is to have fresh air when you want it, not when the weather happens to want to send it in.   The thought of constant or required mechanical ventilation has caused many people to think we're building houses too air-tight, but we think this is looking at the situation the wrong way.  On cold days, its better to run the ventilation fan than to live in a drafty house: on other days you can open the windows.  We say to seal it up as tight as you can, because even if you're pretty fanatic about it, its still leaks air.  

There is a lot of hype out there about various heating systems save energy, but in our view, even if its true, its not worth considering until you've added as much insulation as you can. 

The sun is free, it is ridiculous not to take advantage of it.  Admittedly to take maximum advantage of solar energy isn't simple yet, but taking some advantage of it is just a mater of putting windows in the right place with a proper overhang.  Even in rainy Seattle, our house gets 25% of its heat from passive solar energy .  The biggest obstacle to taking advantage of the sun is that developments plat out land with no thought of providing solar access, and so many homes have their sun blocked.