Why is 'pink' for girls and 'blue' for boys?

I am surrounded by friends who are all having babies and it seems that the only way to distinguish a boy from a girl newborn (other than seeing them naked) is that they're wearing either pink when they're girls and blue when they're boys. Why is that?

According to this Google answer, this associaton is quite recent and in fact at one point pink was considered more of a boy's color (because of its relation to red) and blue was a girl's color (because it was supposed to a paler color). The current association was not uniform (at least in the US) until the 1950s.

According to Wikipedia:

In 1918 "Infant's Department" (an industry publication) said the reverse was the "generally accepted rule", describing pink as "more decided and stronger" while blue was "more delicate and dainty"" Pink continued to be used for both boys' and girls' clothing through the early 1960s, though associated more and more with femininity.

A more gruesome influence, it seems, was Nazi germany as the Nazis chose the color pink (with the triangle) to identify homosexual prisoners in concentration camps. This color was later re-claimed by homosexuals as a sign of defiance. It appears that pink was already associated with girls in Germany in the 1930s.

NOTE: Despite what some people (now in their 30s) may have thought back in the late 80s, I don't think Don Johnson has made 'pink' more manly... Hopefully that dreadful fashion won't be back for a long time.

Aren't we glad times have changed?! Long live the new century.