The people at Physics World have done an interesting but not surprising study on the number of Physics Nobel laureates who are/were immigrants. They found that this number is more than 1/4 of all Physics Nobel winners.
They discussed what they used as a criteria of an "immigrant", and the chart they showed certainly is very clear that there is a huge influx of these talents into the US.
Still, it would be nice to see how many of these immigrants did their Nobel Prize winning work before they migrated. And I definitely want to see this statistics for the next 10-20 years, especially now that they US is severely cutting budgets into basic physics research, the effects of which will not be felt immediately.
In any case, it is that time of the year again where we all make our predictions or guesses on who will win this prize this year. I am still pinning hopes that a woman will win this, considering that we have been having very strong candidates for several years.