Honestly, Agumon's status as a game character is questionable but he comes from a virtual pet, essentially a fighting Tamagotchi. If V-pets don't count as games, where do you draw the line? And why does Mr Game&Watch get a pass when he didn't originate as a character? Or ROB, who was a peripheral?
Agumon is at least as much of a game character as some of the Nintendo characters already in Smash and Sakurai is known to be a V-pet fan. A genre, I might add, that isn't really represented in Smash, despite its historical significance.
I will not vote for either side in this match, as I want both. At this point, though, I do feel like Agumon has more of a chance.