Well you would be under attack without pokemon out so when you do take one out it has to be instantly. More than 1 pokemon at once could also be useful in going against high lvls or more than 1 pokemon.

^^SilentWolf: Amen. You hit it right on the head--My roommate's guilty of this

Each server could have it's own PKMN league, and naturally it would be like a weekly tournament that you must show up for if you have a spot, or else you forfeit.

They could also release updates every few months with new attacks, new dungeons to explore, and new small stories. They would also definitely need a relationship aspect with your pokemon--more in-depth than 'it loves you' or 'it hates you'. (Yes, this would all require a hard drive, but as MMO's require large amounts of space, I'm assuming they'd release one.)

I've always imagined a fully 3d Pokemon, and would definitely buy this, despite being an MMO, so long as it's free. It would be cool having to fight real people instead of the random NPCs that are just standing around in the middle of nowhere in the GB/DS games.

Why yes... yes I would.

Oh if they did make a non mmo pokemon game for the wii they better make it with having the choice to battle npcs or not because that just gets tedious and boring.

It may not happen. If the game is updated every few weeks/months than it would require money to purchase the update or for server maintenance. It's like that on all MMOs. The games have to have fixing and tuning so everything runs smoothly. They could do a Microsoft and make you pay a set price once a year to cover it. My game (FFXI) milks you every month for $12.95+ (+ is for if you have more than one character, which is an extra dollar), but it's worth it due to maintenance and updates. You still have to purchase expansion packs.

But as mentioned, the Wii will need a hard drive in order to keep that large volume of information that's needed for an MMO. We will have to see what Nintendo has in store for the Wii Animal Crossing game.

Oh, and I know how legendary battles would be set up. You would have to go to an area to battle, but it permits only one person at a time to battle the legendary. It would have to be setup like how I have to do Avatar (summoning) battles (but you can have help with higher lvl players if you do the Prime battles, which are Lv65+). After you defeat or capture the legendary, you get sent out of the area and the next person would have to deal with them.

And the MMO would have to involve quests to obtain items and status (fame). The more well-known you are, the more rare items you can purchase or obtain from people or stores.

In trainer battles, as far as I know, those are the rules.  As far as wild pokemon battles, the only times where you fight multiple wild pokemon or fight one pokemon with two on your side, is when you fight with an ally in Diamond/Pearl. 

Perhaps bending the rules to allow a player to fight one wild pokemon with two of your own(or 2vs.4/3vs6) could be possible, however allowing six of your pokemon to fight against one wild pokemon seems like it could make fighting/catching too easy.

 Quick question; Is the Wii powerful enough to handle WoW from a technical standpoint.  I would like to make a list of some ideas that could go into a theoretical Pokemon MMO, and would like to have a baseline of what is even possible on the Wii before I start.