One of the highest ranking government officials in Marvels movie canon as well as the Ultimate Universe is Nick Fury, who is black in both of those universes, but not black in the 616 universe. Notice how Sammy J didn't even really act when he appeared in the Iron Man films, but was just sort of playing himself, not the Nick that comic loyalist have grown to love. That bugged me far more then anything else in the film, but still people didn't complain about it. Spidey is a little different what with public perception of him being more... concrete. I don't think Spidey has ever been black, he's been Japanese twice, old, Indian, a teen, and Latin in 2099. So this would actually be a first.
How I feel about it... I don't really care either way, mostly because I was disgusted about why Sony made the revamps in the first place, to keep the franchise out of Marvel Studios (The Incredible Hulk, Iron Man and it's sequels, and the upcoming Capetian America, Punisher War Zone, Thor, and Avengers films) hands. Fox owns Daredevil and Fantastic Four and I hear rumors of them attempting the same thing. So long before any news of casting and lower budget then the previous films I wasn't a fan of the idea of a reboot solely to keep a property.
At the end of the day though, it's a movie, and if race TRULY doesn't matter, then the part should go to the person best suited for it, race aside.