what is up with all the Blackface in Hollywood?

now on Saturday Night Live they have Fred Armisen in Black Face as Presidential Canidate Barack Obama. thing is simple to me, can't you hire a Black Actor to play the role? yeah it bothers me and makes me think of Al Jolsen and Birth of a Nation where Black Face roles and films were the norm and accepted. I remember a little over 20 years back and the film "Soul Man" with C Thomas Howell in Blackface. and now in the latest Ben Stiller film Robert Downey Jr is gonna be in BlackFace. I mean Hollywood has control over the Black Images that blow up on the big screen and small screen and to keep this mess going on is just a mess. I don't find it funny and I find it racist and in poor taste and this is still going on in 2008 and there is no outrage and I find that scary. those images of the past still haunt and hurt and they hurt even more now because it is being accepted and taken without being spoken out against fully.