He's speaking at a HBCU to a largely if not all black graduating class. This isn't Stanford or MIT. I know theres a blind spot to the inequality African American students face and that this is a sensitive issue, but I don't think telling African American students who are graduating college to be wary of a lot of the distractions these days such as xbox and twitter is a bad thing.
I could go on for a bit about why, but Obama lays out the statistics for you...
American students are ranked about 10th overall compared to top-performing countries. African Americans, however, are ranked behind more than twenty nations, lower than nearly every other developed country.
I would say that Obama is inspiring a generation of African Americans to work harder and strive for more because inequality is still pervasive throughout American society and education is the key to overcoming this. Why is it so hard to miss this message?