I fight the thermostat battle with my fiancee all the time. She likes it cold in the summer. If I turn the thermostat up, she complains that it feels like a sauna. I guess the plus though is that she likes it cold in the winter too...

One interesting point though. The primary job of AC isn't to reduce the temperature - it is to reduce the humidity, which is easily done by chilling the air. A malfunctioning AC system can chill the air but not enough to reduce the moisture, and this leads to a cold and clammy feeling. I am inclined to think that the thermostat ought not blindly use the temperature as a target, but use some combination of humidity and temperature to reach a certain comfort level. Thus on days when the air is warm and dry the system doesn't have to work so hard.

I've heard that in the US sometimes room temperatures are even lower in summer than in winter - is this true or a legend?
Ya'll got a problem with that? Talk to the gun!

I'm sad to say that this is at least the case in Canada too.
Many a day, in the summer, I'm wearing a long sleeved shirt and long pants - because it's cool - and I'm passing house after house with the A/C running. At home we don't have A/C, don't see a point in A/C because we only get short stretches of hot muggy days now and then. The deck is shaded so eat outside on it and if the upstairs gets too hot to sleep in (>32C) then just move down a floor or three (I'm usually not able to tolerate the basement - it's too much of a temperature shock).

It's individualism and isolationism. People go around sealed in their cars, or they're sealed in their buildings; rarely experiencing the changing temperatures. Offices at work have people wearing winter clothes because the A/C is set so cold. Mostly the problem at work is that there is very poor control of the cooling - so people in some areas wear sweaters in the summer.

Certainly as one gets older one seems less tolerant of colder temperatures and I've been in buildings where
the temperature must have been around 25C in the winter. We keep our home around 20C daytime, 16C nighttime ; although I know people in upstate NY which keep their homes around 16C daytime and they can tolerate that - but it's too cold for my fingers to do work.

I have co-workers who refuse to "freeze in the dark". Translation - they leave all of the lights on in labs that are not being used, leave the heating/AC going full tilt and will not even consider turning off half of the lights. In comparison I never turn on the heating or cooling in my office and replaced the 800W of lighting with a 40W CFL. The fan for heating/cooling uses almost as much power as my home. The lights use as much power as my home. The rooms I manage, each, use around 5x to 10x the power of my home. Around here, anything that I do will swap what 10 of my neighbours and I can do. Paybacks at work are sub 1 year (esp. for things like upgrading computer power supplies to 80Plus spec ones like Antec) for efficiency upgrades while those at home are >15 years. CFLs have only started taking off recently; but I remember them being all over the place in Scotland around 8 years ago. Over there, water heaters hang on a wall and vent into the room; around here an on-demand water heater is 3x more powerful than my furnace and costs thousands to install and have to vent thru a wall (which greatly limits where you can install them). I've got relatives that can shower in 80L of water. That's enough water for me to shower daily for 8 days and wash all of the dishes for my family for those 8 days. This is a relative who is working to build a "green" home - and they'll suck my 19 gallon water heater dry with a single shower.

Energy over here is so friggin' cheap it's amazing. With gasoline around $6US/gallon I still don't bother thinking about using the car - because the cost of purchase, ownership and insurance swamp fuel costs (well I commute by bicycle). Dito for the home. With taxes running almost $3k/yr and energy costs only around $1k/yr there simply isn't any reason to do anything to save energy. My monthly phone bill is nearly 2x my electricity bill. If I had a Blackberry that would make my electricity bill look cheap too.

I hear about homes in the USA that will take $5k/winter to heat (oil) but just can't believe it as my home (15 years old - standard subdivision home) is around $350/winter +$200/yr connection fee for gas). Then again I was just working on a farm and they burn 20 cords of wood per winter for heating/cooking.

Drillo,

"I've heard that in the US sometimes room temperatures are even lower in summer than in winter - is this true or a legend?"

Sometimes it is, but it depends on the individuals. In the Winter I like keep the temperature down and to dress warmer. My friend complains that one of his kids turns the heat up to about 80F (?)28C(?).

In the Summer my problem is with these big office buildings where most of the air is recirculated. It feels stuffy to me. I like windows that open. Also - as you mention - it is a shock if the difference between outside & inside temperatures are too great.