http://www.newyorker.com/talk/content/?051128ta_talk_surowiecki contains a comment about French productivity being as good as American.
BUT: this hides something, which is surprising given the rest of the article. In France, the labor market makes it inefficient to hire low skilled workers. French productivity is artificially high, in a sense, because many low skilled workers aren't in the market at all (hence 10% unemployment, raging youth unemployment, etc--the French model also protects existing workers at the expense of those trying to break into the market). So from this perspective, American productivity might actually be higher than it seems at first glance.
(This is not advocacy of any particular economic model: I think both the Franco-German and American models have major flaws. A system in which 10% of the population don't work at all is not something to be proud of, even if there's a coddled class of workers with 35 hour a week contracts and 6 weeks vacation.)