What is the best Pokemon MMORPG?
There is no such thing as a Pokémon MMORPG, although the idea is insanely cool. The closest thing would be to either play Pokémon Diamond/Pearl for the DS using the WiFi connection, or download BattleNet, an online Pokémon battle sim. If you meant what is the best Pokémon GAME, I think the Diamond/Pearl games are the best, followed closely by the Ruby/Sapphire generation. It just gets better every generation.