The fact that this video was on
www.wii.jp means that anybody who doesn't believe it is being silly, IMO.
That said, this bodes ill for Ness. What with the whole "no clones" thing, he'll have to have an entirely new moveset, and the most likely one would be a moveset based on the abilities he
actually had in EarthBound, and not attacks randomly taken from Paula and Poo.
In other words, I'm pretty sure he'll keep PK Flash (that was his to begin with in EB), but he'll lose Fire, Thunder, and Magnet. Going by his EB abilities, he'd likely pick up Life-Up (or perhaps Heal to be more fair), Teleport as a new Up special recovery, and perhaps Hypnosis or Paralysis as his third move (something akin to Mewtwo's Forward/Down specials). If he got a moveset like this, Flash would become his only major attack, turning him into a primarily defensive character.
I imagine his Final Smash will be either PK Rockin' or Lucas's PK Love. Rockin' makes more sense, but then, Lucas got Starstorm, which wasn't as powerful an attack as Love, and not even
his attack anyways (Kumatora had that), so I wouldn't be surprised if more attacks got flung onto people that didn't actually have them in their source games.