I think this is probably a good idea. Fred Armisen did an admirable job trying to portray Obama even getting many of his speech patterns and mannerisms down. But in the end, I kept seeing a white guy in blackface.
Armisen came trough in a pinch, but SNL really needs someone who can do the job "full time", as it were. I mean, Obama is going to be around for awhile and for some reason SNL has become the political satire gold standard on TV. So they need someone good if they expect all the cable news networks to replay their Obama skits endlessly.