When I look on Facebook pictures of my european friends, they tend to be in a big mix of colors. Sure, there's more Indians at an Indian wedding in London, but you will see the little gang of white/east asian/black kids there too. Go to a majority (ie white) wedding and you will see they have a bunch of Indian/Chinese/Black etc friends.
When I look on the Facebook pictures of American friends, they are quite clearly color segregated. I really find it odd that out of maybe 300 guests at a wedding in SF, only a couple are not from the same minority.
America is also the country where I've found the strongest racial stereotypes. In Europe it's not really the stuff of comedians anymore, but when I went to a comedy night in NYC, the guy looked at me and said "Why aren't you doing homework?". Funny, sure, but it says something about what the audience already believes about various people.