Culture shock is always something to think about when taking a meeting overseas, but this is pretty extreme: Paris Syndrome. According to the article, some Japanese tourists find the reality of Paris so far removed from their expectations that it actually can cause psychosis:
"A third of patients get better immediately, a third suffer relapses and the rest have psychoses," Yousef Mahmoudia, a psychologist at the Hotel-Dieu hospital, next to Notre Dame cathedral, told the newspaper Journal du Dimanche.
If you have any fragile folks in your group, I guess you better be careful in how you market your destination, be it Paris or Pittsburgh.
(Thanks to the MeCo listserv for the pointer.)