Pokemon wins hands-down.
Digimon is pure job. They digivolve when it's most convient, then go back to normal. I have to admit, digimon has a more solid argument for evolutionary basis. Exhaust too much power, and they "de-evolve" to a more primitive step. One that involves a talking head that spits bubbles and takes a pink shit.
However, pokemon could easily beat the crap out of digimon. Here's an example.
Charmander vs Augumon.
Augmon: Pepper breath!
*Charmander is resistant to fire damage*
Augumon: Oh snap!
Charmander: Char-Char!
Augumon: That..that's not even a word!
Charmander: Chaaaar! *Uses ember and Augumen whines for Tye*
Charmander: Charmander Charmander Charmander!
*Uses scratch at his face*
Augumon: Alright Alright! I'm your *****!
Digi-evolution might be more convient, but they cannot digivolve on thier own without thier trainers. (Or they can, but it's extremely rare) Like I said, thier evolution system makes more sense. But pokemon is just better.
people dont know their digimon,
the most powerful : yggdrasssilmon{god of the digi multiverse anc creator of it}
second: wargreymon burst mode{stood up to yggdrassilmon}
third: susanonmon{destroyed lucimon, the god of the digi universe who cud destroy it as well as the normal universe}
4th: lucimon{see above}
5th : galantmon crimson mode{defeated reapermon}
6th: reapermon {cud also destroy the digiuniverse}
now it gets a bit hazy with lots more coming in. we have maotaimon, beelzemon, the celstialmon from the movie, sumethin sutmthin mon -paladin mode{from the second series}, apocalymon, omnimon, etc etc etc. we also have the time stopping one with really long hands ad dark wargreymon and the the dark one that teleports etc etc.
in short, digimonsters blow away pocket monsters. they are some of the most powerful creatures ever created in anime. sum might even stand up to tenchi muoy or lord of nightmares.