I guess my general problem with this is that when I hear "Blackface" I bring to mind pictures and images of the 'old' days in the theatre, with white people in pitchblack face paint with white lips or eyes. I look at something like what Hough did, and see that her dressing up as a specific person, not a race.
But then, I don't have problems with people painting themselves all blue and calling themselves Smurfs or Na'vi, either. Or all green and going as an "Orion Slave Girl" from Star Trek. I understand it's a costume, and generally of something that the person dressing up as them really likes.
I don't see dressing up as Justin Timberlake a problem (I laughed), or Jay Z (though it's not really like he's got any sort of recognizable style, that one's iffy) or Houghs costume (Suzanne Warren) as any problem. Hell, I didn't even recognize her AS Houghs until it was pointed out and I saw a bit of white at the top of her forehead. To me, there's a world of difference between that, and the intentional idiocy represented by the 'original' style of Blackface.
I hear "Blackface", and this is what I'm thinking
Spoiler for poss. offensive image:
The pics shown in this thread don't even come close.