From NPR:
Census figures show the Hispanic population in the United States now accounts for more than half of the nation's growth in the past decade. But how to classify and measure Hispanics in the Census is complicated, since they are an ethnicity not a race. Ruben Rumbaut, a professor of sociology at the University of California at Irvine, talks to Steve Inskeep about the predicament.

Audio link available at http://www.npr.org/2011/03/30/134974387/Race-Among-Hispanics?ft=1&f=1015...

Also ran in:
    Oregon Public Broadcasting News
    WBUR 90.9 FM
    WFAE 90.7 FM