**smiles.** You know what I'll say, right?
YuGiOh, IMHO, is much better than Pok?mon, anime-wise at least. The stories are better, more serious, and the characters are more interesting. I don't like how Pok?mon sometimes relies on almost a Warner Brothers-ish humor, i.e., people getting hurt and it's meant for laughs. When people get hurt on YGO, it's a serious matter.
Sorry, I can't compare the two where the other aspects of the fandom are concerned. I haven't read the Pok?mon manga (the YGO one can be kinda disgusting at times, though, but I do have an extreme respect for the creator, Takahashi-san) and I don't religiously collect the cards or the video games. I did play some of both Pok?mon Leaf Green and the first YGO Battle City related game and I liked them both. ^__^ If I ever get the money to buy a gaming system, it's gonna be GBA.