The economist has a piece about how much American kids study (http://www.economist.com/world/unitedstates/displayStory.cfm?story_id=13825184&source=most_recommended) that starts with the requisite clichés about the lazy French.
Did you know that the French are the fifth most productive people of the OCDE, before the US and way before Japan?
It's true that the American work on average 11% more than the French but did you know that on average the French work more (and better) than the German?
Interestingly, there seems to be an inverse correlation between hours worked and productivity: the less you work, the better you work.
Other data seem to indicate that the French *are* the most arrogant on the planet though, and this post can only reinforce that. :)
Source: OECD http://stats.oecd.org/Index.aspx?DatasetCode=LEVEL
Update: David sent me some interesting additional data (see comments if you can read French) that shows that although Americans still work around 40 hours a week in the industry, the picture is very different when you look at the whole active population because of the lack of stable jobs. The average then falls to less than 34 hours a week (White House data for 2007, which corroborates the OECD data) and still steadily falling. It's even worse in Great Britain (less than 32 hours a week). Also interesting to look at is the average length of work for French people who are working full-time: 39.2 hours.
What this tells us is that the average length of work does not just come from regulation (the infamous French 35 hours) but also from the general social and economical climate (the amount of stable, full-time jobs). The end result in terms of quality of life can be drastically different even though the figures look close on first analysis.
It is of course also relevant to look at the repartition of the GDP, which is something that the above statistics hide. If there is added productivity, who reaps the benefits? The answer is that only the top 5% American salaries have raised over the last five years. It is doubtful that it is those 5% that are driving all of the productivity increases.
Finally, another interesting data point is that according to Eurostat, France is the country that saw the greatest increase in productivity since 1980, with a whopping 2.2% increase.