I'm curious because I just watched Nintendoland: zelda Battle quest demo,  its looks like it should work with 2 wii Pads i.e 2 people play as archers (U-pad) whilst another 2 play as swordsman (wii-mote)?

Also games like Fifa will unfaire if one player has the U-pad and the other has the less accurate wii-mote set up.

I don't think there's any games that will support 2 GamPads at launch, unless they confirm games that will next week's (September 13), Nintendo press event. We will see soon enough.

not as of yet

They said at E3 that none of the launch games would.

To be honest, it gives the impression that the inclusion of the 2nd controller was an afterthought given our complains.

this.

also why i think the gampad takes up a decent amount of processing power.  if it was really easy to have two or more gampads interact with the system it would have been added long before the complaints.

But even if it was an afterthought, the inclusion of 2 U pad requires almost no effort on devlopers behalfs, its the sort of thing that in most cases can be done over night. Naturally  the 2nd  pad would have the exact same input as the 1st (no effort here), the only thing they have to do is manage the ram resources; dropping frame rate for games running at 60ps, droping the screen resolution from 1080p and managing graphical degrades if none of the above is enough or (anti aliasing, motion blur, textures qualit etc).

I guess because its launch everyone is just trying to get their games finished.

I don't think this is necessarily the case.  I think nintendo hardware designers were so focused on the idea of assemetric gameplay that the idea of using 2 wiipads together didnt' even really enter their mind; or they scratched the idea because they wanted to maintain 60fps on the TV and the pad.  After just about everybody asked the question "can you use 2 pads at the same time" they realized that it was a feature that most people were curious about and decided to make the required compromises to make it happen.

..other than completely change the nature of the gamplay.

the first 2 U pad game will be absolutly no sooner than 1 year after nintendo's announcement to developers that 2 gamepads are allowed.  2 years for a high quality game.

if that's the case then they really weren't thinking very hard.

and (off topic) i'm really not thinking the asymetric gameplay is the way to go here.  asymetric gameplay isn't a new concept...but the games that have employed it always fall into the same trap.  when two players are playing the same game one persons game is always more fun than the others and no one wants to play the short end of the stick.

But why would it change the nature of the gameplay? Of course its completely dependant on the game, but with the 2 cases I mention Fifa and Zelda battle quest the gameplay should remain exactly the same. Fifa uses the Pad for more accurate passing, shooting and player management during a match. How would this change for 2 control pads? It will just provide both players this perk as opposed to one.

Equally Battle quests has people with the pad take on the role of archer, including 2 archers will make very little difference to the game. 

Developers will play around with assymentric gameplay but more traditional multiplayer will still be the most dominant imo. This means providing both players with the same control options.