I've kinda been crazy about this game ever since it's been announced.
But the first PSP game to use Full Wifi Online Gameplay is Phantasy Star Portable 2. Which is a port of Phantasy Star Universe.
How it works is that it will not have a Monthly Fee and the UMD will come with a serial code to activate online play which would be on the back of the instruction Manuel.
How Online Play Works:
You start out by selecting which character you want to use and you select a player created room, which is like a party of 4 people to do dungeons and quests, it will always include:
. A huge lobby for you to explore and to use voice chat.
. Daily Updates and Monthly Misson/DLC updates.
. Customizable houses/rooms with any kind of furniture you want :
^Player Owned Shops,
TV Commercial:
I think this is quite impressive for the PSP and to have a Real Mmorpg on it.