I have tracked down another Pokemon MMORPG but this one doesn't seem worth trying. Someone left a comment saying to try out Pokemon Mystery Dungeon Hunters of Life. I have tried to register to be able to play but I never receive a email to be able to confirm my address, so I can never be a member of this free Pokemon online game.
The idea of the game seems pretty good as normally these online games you play as a trainer only but the game gives you the option of playing as a Pokemon trainer or a Pokemon character (I guess just like an online version of Pokemon Mystery Dungeon).
There are a few pictures showing the maps, they look good and they say it is an original Pokemon storyline with 20 complete game chapters. It seems like it has a number of members (not sure how many) playing but without being able to log in and play online against others I can not really say how it is.