Not quite: Dana Carvey tried one already. And then there's Fred Armisen. But you have to hand it to Tim Wilkins (former host of Studio 10, the Channel 10 morning show): His impression is actually good (though with just a hint of Tricky Dick).
As for black comics' impressions of the prez-elect, check out this radio guy.
This article appears in Jan 14-20, 2009.