It's undeniable that Digimon is better than Pokémon as a TV show, the sole fact that Pokémon has Ash in it makes Digimon the better one. Pokémon has the same 700 episodes by now, only unique one is the one where the Pokémon have stranded on an island and there's subtitles for what they say. While Digimon has sucked ass ever since the first series it still had a much better series just by the first 54 episodes of the first season.
It simply had a darker and more serious plot. Digimons had personalities, there's only one episode where we understand the Pokémon, excluding the tons of pointless movies which were erased from the cast's memory the next episode anyways. Digimons actually die in the series, even good ones, there's not even close to anything known as death in Pokémon, at most the Gastly->Haunter->Gengar line is the closest to death mentioned in the series.
Also, it had a much better movie. As a child you basically looked upon Omnimon as a god. And while the Mewtwo movie was cool and all, it just didn't stand up to the raw action of Our War Game, which btw only lasts about 40 minutes while the Mewtwo movie lasts about 1 hour and 30 minutes. All the other Pokémon and Digimon movies ended up sucking big time though.
Digimon was ruined as early as the second season though, it completely bastardized the first season, and it's sitting down there with Pokémon now. Still, it had one good season, and that alone makes it the victor.
However, the Pokémon games are of course the better ones. Digimon had Digimon World 1, and then a bunch of good to okay games, while Pokémon has had at least 3 amazing games, with only 1 bad, not counting the spin-offs.
Pokémon Red and Green were released in Japan in 1996, Digimon in 1997. Pokémon were the Gameboy games, Digimon was made as a Tamagochi for a male audience. The TV series weren't able to rip each other off though, seeing that both aired for the first time within an hour of each other, Digimon being aired an hour earlier than Pokémon.