I would want a game that the Trainers have more of a role inside battle than just giving commands. I had ideas of the Trainers being able to battle Final Fantasy style against the other trainers. I was writing a fanfic like that, but it also had Final Fantasy stuff within it such as the monsters, jobs (for the Trainers), Moogles, Crystals, and Pokemon, but I got too caught up and busy to ever finish it Like a Dragoon fighting along side a Charizard or Dragonite. Thieves would have Sneasels or any other sneaky Pokemon, White Mages having Chansey/Audino, etc.

EDIT: Crystals were used to synthesize Technical and Hidden Machines (in my story), and there would also be items that the Trainers could gather in the natural world to create medicine, food, their own clothing or armor (weapons to fight monsters that were in the wild as well that target Pokemon, such as undead, archaic, magical, beasts, and common monsters from Final Fantasy), held items for the Pokemon, gear (such as a backpack to hold more items, gear to swim underwater to catch Pokemon, etc.)...

Moogles were hidden creatures that enabled Pokemon to use hidden strengths and abilities. They would merge with Pokemon and add strength to them. Trainers would have the various roles and jobs from Final Fantasy (I used the ones from Final Fantasy XI and XIV in the story, but only XIV from a later date).

EDIT 2: Crystals came in elements of Earth, Fire, Wind, Water, Lightning, Ice, Light, and Dark (taken from Final Fantasy XI). Earth is to bind, fire is to burn and cook, wind is to cut, water is to dissolve, lightning is break apart/strip, ice is to cool and chill, light is to repair and restore, and dark is to decay.

Everyone here does it.

I.E. They all said WiiMusic sucks balls. Therefore, I bought it when it was recently released and still hadn't bothered opening the box still. WiiMusic sucks balls.

A Pokemon MMO doesn't have to play like or compete with Pokemon _____ colour.

Pokemon is an incredibly versatile series as we've seen with the various spin-offs; Rangers, Snap, Colossium, Pokepark, etc.

Nor does it have to be World of Warcraft/Pokemon-style.  There are a broad range of MMO models and I expect Nintendo would do it's own unique take.  Something that would encourage physical elements as well - walking, being in proximity of other players in real life, StreetPass, etc. 

@irstupid - A barcode idea might be more practical, yes, but not as much fun.  They could play with both ideas really.  Slap a giant 'AR Card' in the middle of a square or on a billboard or wall so dozens could use it simultaneously.   The crowds would draw crowds to see WTF was going on.

@ immortal - Even 10% of the pokemon market is quite sizable and worthwhile.  Heck most MMOs would love a base that big.  However, it doesn't need to be a pay every month model.  Could be micro-transactions or instanced like Guild Wars (pay only for the game, not the online), or something akin to Monster Hunter's model.

This would be awesome if it were true. I'd pick it up in a second!