I'm not going to link to any of the articles published in the last few days about how no one likes changing the clocks to and from Daylight Saving Time. Suffice to say, the debate hinges on two simple questions: how early do you want the sun to set, and how late do you want it to rise, in winter?
For a concrete example, if you live in Chicago, do you want the sun to rise at 7:19 or 8:19 on January 3rd (the latest of the year)? And if the sun rises at 8:19 that morning, is that an acceptable price to pay for the sun setting at 5:20 (instead of 4:20) on December 8th (the earliest of the year)?
A switch to year-long DST would mean that the sun would rise over Lake Michigan after 7am from October 12th until March 17th—five months of morning gloom, offset by the sun never setting before 5pm.
On the western edge of US time zones, the results would be truly weird. Just across Lake Michigan from Chicago is Benton Harbor, Mich. Year-long DST would make the earliest sunset there occur at 6:14pm. But the latest sunrise would be at 9:14am, with the sun rising after 9am from December 7th through January 31st, and the sun rising after 8am from October 17th through March 14th. After 7am? August 22nd through April 19th. Yes, permanent DST would relegate places like Western Michigan, Western Nebraska, and Idaho to nine months of gloomy mornings.
Ultimately I think this is why the permanent-DST proposals will go nowhere in the US. The parts of the US most sensitive to late sunrises (farming areas) will be the ones most affected.
And hey, won't Spain be fun when permanent DST comes to Europe in two years. The sleepy town of Pontevedra, Spain, on the west coast of that country and at about the same latitude as Chicago, will enjoy sunrises at 10:04am in January should Spain go permanently to UTC+2. (But hey, the sun will never set there before 7pm, so maybe that's a good trade-off?)
Of course, this is all about psychology. The sun rises and sets on its own; only our need to agree on time causes these odd artifacts. Maybe in western Spain they'll simply start work at noon? (Or, more likely, switch to UTC+1 year-round.)