The topic of US vs. European work vacations is something that pops up every few months or so.   Most recently, MSNBC had the following to say:

THE UNITED STATES MAY boast the world’s strongest economy, its most influential popular culture and biggest military, but in at least one respect life in the United States falls short of other industrialized nations: Americans enjoy less vacation.

This reporter seems to do a better job than most other accounts I've read about the "issue".    The usual litany is something along the lines of "Americans are exploited by their employers who take advantage of our job insecurity and rapacious, outsourcing-around-the-corner, globalized capitalism....   Governments need to do something to help us claim a more sane, vacation schedule like those enlightened Europeans."    Well, maybe not so directly.

As much as the vacation issue reveals subtle biases that influence reportage (how the US "falls short"), it also brings to bear several important differences between US and European perceptions of work.  

• Stated vs. Revealed Preferences -- There's complex causality for why American take fewer vacation hours -- especially since they aren't even taking the vacation time they're alloted today!  The article states: 

  Americans were allowed an average of 16 vacation days in 2002, but most only took 14 days off, handing back more than $21 billion in unused vacation days to their employers.

  If more vacation time was really the cure for whatever it is the reporter thinks ails us, our "used vacation hours" should be redlining right up to the limit.
• Preference for Salary & job churning  -- international comp analysts & corp HR departments frequently point out that average American workers generally choose a job that pays a few extra $K per year over one that offers an additional week of vacation time.   Vacation time hardly matters, if at all, when the worker is choosing between 2 completing job offers.   By contrast, if a worker expects to stay at the same firm for a significant period of time, it's more likely that he will "game" additional benefits like vacation time from his employer
• Higher Pay = Longer hours -- even when you apply statistical games to tease apart causation -- e.g. people who are incented via overtime pay -- the fact of the matter remains that for most Americans, the more highly trained / lucrative your profession, the MORE likely you are to be working greater 40hrs / week (techies in silicon valley, execs, docs, lawyers, etc.).   For example, this article point out:

  Indeed, that pressure to perform may have flipped the hourly balance. “It used to be that when you got a college degree you could get a white-collar job and take it easy,” Kuhn says. “It’s just the opposite now. It’s blue-collar folks who have more time for leisure.”

  Clearly, for the white color types described above, work isn't something that's simply used to pay the bills and fund leisure time afterwords.   Work, and the sense of accomplishment that stems from it is actually crosses the boundary into a sort of entertainment.
• Demographic -- American workers are as a whole younger and thus more likely to fling themselves at the office with reckless abandonment;  less likely to have family obligations;  more likely to feel like they're on the upward curve of their work ambitions rather than on a plateau
• Belief in Economic Reward -- American's are more likely to believe in the short term & long term results of working hard particularly class/income mobility -- I LOVED this survey, for example:

  During the most recent presidential election a Time magazine-CNN poll asked voters whether they were in the top 1 percent of income earners. Nineteen percent reported that they were, and another 20 percent said that they expected to be there one day.