You all might be interested in the following
New York Times article about how recent immigrants to the USA are much more likely to be keeping their original names than they were in previous generations:
http://www.nytimes.com/2006/10/12/fashion/12names.html?pagewanted=1&_r=1&ei=5087%0A&em&en=3de7557bf8644fcb&ex=1160798400