But then you have to account for the higher cost of living, transportation (even if you don't drive, French employers pay for a part of your public transportation tickets), and all the other perks that are inherent to your job (insurance, subsidized lunches,...) and inherent to the country (better public education, etc.).
So I think it's hard to say empirically that engineers are better off in one country rather than the other- although I'd be tempted to say that very high end engineers are better off in the US rather than Europe, and the average engineer is better off in Europe rather than the US.
...better public education...
Um, no. Better students, but a considerably worse public education system.
The cheese, however, is considerably better in France, as are the women (fatties over here drag our average down).
 Since I'm too lazy to switch to windows and open up the Penn Table in Excel, I backed the numbers out of GDP tables: http://en.wikipedia.org/wiki/List_of_countries_by_GDP_(PPP)_... http://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nomin...
[edit: Hi downmodders, sorry for providing facts. I'll try to avoid that in the future.]
Based on my very subjective experience living in both countries (France growing up + undergrad, US as a graduate student+working), I would say much depends on the size of the city where you live.
Living in San Francisco definitely costs much more than living in Lyon (2nd largest city in France) for me- if you look at the apartment alone, I'd have to shell out $2k+ for something I'd easily have in France for under a thousand euros in terms of size + proximity to businesses.
But then for the food + basic expenses (clothing, etc.) I feel like I spend about the same, although some things are more expensive in the US (public transportation, cell phone plans,...).
When I lived in Grenoble I lived a comfortable student life on 1000 euros a month- this would be nowhere sufficient to live comfortably with in SF. But of course the cities are of different sizes, so again this is very shaky grounds for accurate comparison.
I don't want to end up posting a novel here, but it's definitely an interesting topic on which I'd love to hear more insights from european expatriates in the US (or the opposite).
As for the cheese, you are completely right– and regarding the women, I don't want to belittle my fellow French women, but I would be lying if I said I hadn't found delightful ladies in SF :)