I tend to think people shouldn't put too much stock in things like the labor force participation rate or the employment:population ratio as an indicator of economic health. I'm a fan, unfashionable as it is, of taking the unemployment rate at face value. But most people seem to disagree with that these days, so read Felix Salmon or Mike Konczal if you want to get your daily dose of hand-wringing.
But I do think that if you want to look at things through this participation lense it's important to take a global perspective. Conventional wisdom has it that the labor market in low unemployment Germany is currently quite healthy. But emp-pop says that there's been no time in all of recorded history when the German labor market has been as healthy as the U.S. labor market was at the depth of the recession. Conventional wisdom also says that Sweden make a comeback from the Nordic Financial Crisis of the early 1990s and learned valuable lessons that helped it whether the Panic of 2007 much better than the world's larger industrialized countries. What emp-pop says is that Sweden has been in a persistent depression for the past twenty years.