Sotomayor, with two other judges, had sided with the city of New Haven when it decided not to promote firefighters who scored the highest on promotion examinations because of their skin color. In its decision, the Supreme Court held that the City could not rely "on race to the detriment of individuals who passed the examinations and qualified for promotions."
Unfortunately, this decision was not unanimous. Instead the four liberals on the Court sided with New Haven's discrimination on the basis of race - probably because the discrimination was directed against white men. Thankfully, Sotomayor's presence on the Court would make no difference. She would replace on of the four liberal dissenters.
As long as Anthony Kennedy, Antonin Scalia, Clarence Thomas, John Roberts, and Samuel Alito can hold on, Martin Luther King's dream that people would "not be judged by the color of their skin" is alive.
(For a local angle, check out this excellent story by Jeremy Kohler in the St. Louis Post-Dispatch. Kohler reminds us that when faced with the identical issues, St. Louis, eventually, did the right thing.)