Summary of this article: economists at UC-Berkeley propose that DST provides no "energy saving benefit", by studying recent experiments with DST in Australia (instead of relying on 30-year-old data that supported the recent extension).
The most troubling part I find about the article is this quote:
In the 2005 energy bill, Congress calls on the department to report whether energy consumption drops, as hoped, after the early start of DST. If not, the bill has a provision for the country to return to the old daylight savings calendar. Under the previous law, standardized in 1986, DST began on the first Sunday in April.
So, if I read this correctly, it means if they find energy consumption does not drop as expected, they could change DST back to the prior dates, and we get to go through the whole time zone update thing again.
My guess is that most studies will find no measurable savings in energy, but the politicians will find one that does, and they'll declare victory. More likely that, than to admit they made a mistake, and oh by the way, all the money you spent in adjusting your various computer systems for the new rules was not only a complete waste, but you have to do it all again to change it back.
Last I had heard, this was also going to cause problems with Canada, as they would be out of sync with the U.S. for three weeks out of the year. However, I just checked, and it seems they are following suit. In fact, this site refers to it as the "new North American standard". I would think that, if I were Canadian, that would piss me off to no end, to have the U.S. dictate Canadian time zone policy.
But the whole Daylight Saving (saving nothing; "shifting" is more appropriate) thing pisses me off anyway. Heaven forbid people actually adjust their schedule to get more daylight time when they want it; no, we have to shift the measuring of the cosmos. I'm sure if they could find a way to actually slow the earth's rotation just to get an extra half hour of daylight, they'd pass that into law, too, with no thought to the consequences.