I always like it when my first reaction shows up in another's comment.
I think it is pretty simple minded to put every quotation of King or the civil rights movement as a discussion of race per se...
To invoke Dr. King is to push for social justice by staking the moral high ground. Dr. King's insistence on non-violence and his ability to appeal to conscience were important elements of his success.
In a day and age when we are abandoning the moral high ground at an alaming pace, Obama's call is refreshing and extrordinarily pertinent. And it has very little to do with "race".