A more casual form of sumo. Over the Internet, communication can be directed to anyone in the world and it's anonymous. It doesn't really get aggressive. It's an intricate style of communication. It's interesting, because in Japan, everybody goes for Pikachu.
American kids seem to like that.
In America there are more products sold with Ash and Pikachu together, not just Pikachu alone. Pikachu is sort of marginal in the game. But it's now the best-known character. When they did the anime, they wanted a specific character to focus on. Pikachu was relatively popular compared with the others and potentially both boys and girls would like it.