Well, we now know those are confirmed. But we've yet to see confirmation that Dr. Mario, Dark Pit and that Stupid Dog™ are really in. This leaker was apparently the one behind that Palutena leak last year, and that one actually was fake even though Palutena did indeed make it in. He could be screwing with us, using a mix of real and fake material to throw us off.
I'll be really sad if I don't get a 3rd DK character, though. :'(