Arcade card games have been around in Japan for a long time, but just starting to hit in the US...
I feelbthey should be under gaming, as some have tabletop and arcade game play rules. For the arcade game, the arcade screen actually has a scanner that you scan the card into you "deck", and you win more cards. Some of these games you can buy decks separate, and others you can only get cards by winning them in game and the arcade dispenses them...
I know some gamers don't consider these CCG/TCG's, and in Japan "Arcade Game Cards" are their own completely separate catagory. I think for now, here, they should be added to gaming. Just as Top Trumps is in gaming, even though its not a CCG/TCG/OCG.
I'm not a hoarder, it's a "collection"....
Joseph