Well, what's different about Payback's description from Revenge's?
It's clearly not a blast of energy, as it's a physical attack. Until Gen VI I would have assumed that the Pokemon was tackling the foe with power stored from earlier in the turn. And even then, it's just sort of hard to determine
And I meant the same based upon their names and descriptions. Aside from Revenge's animation being clearly a punch, as opposed to Payback's somewhat unclear nature, they match up (Or that was my original argument, as it turns out, there are several mechanic based arguments for their difference. I was simply only worried about the theme at the time)
Shadow Sneak does not have nearly the same description as Quick Attack, does it? Or a name that's nearly synonymous with it?
Also, the BW animation for Payback shows the user gathering energy (like Strength or Bide) before proceeding to beat up the foe violently (I think it's the same in Gen 4 too?)
And as much as I hate referring outside the games: In Pokemon Adventures the Pokemon clearly makes physical contact with the foe in an apparent tackle (Though again, outside the games, so not worth much outside a mention imo)