At the moment, there’s no announced games that support the use of two GamePads. You won’t even be able to purchase a second GamePad from retailers. Reggie Fils-Aime has assured people, however, that:

The reason you don’t see games with two GamePads [at this event] is the technical ability to make two GamePads work was delivered to publishers after they started this current round of development.

(This is actually consistent with a rumour we heard a long while ago.)

And:

…you’ll see those two GamePad experiences at a later date; when those games are coming, that’s when we’ll make a separate GamePad available.

Of course, this won’t make the GamePads any less expensive. That might restrict the amount of two-GamePad experiences we see.

http://wiiublog.com/there-will-be-games-that-support-two-gamepads/

Good to hear. Hopefully they make the controllers cheaper by that time.

I suspect a small handful of games might offer two gamepad support as an option (never a requirement), more for your friend to bring their's over than for you to own two.

I can't see anything else happening, because no one builds a game for a market that doesn't exist.

nah, they'll probably bundle it like they did Wii Fit, when the HW becomes cheaper to manufacture. With so many U's predicted to be sold, it should become fairly cheap to manufacture the 2nd controller.

When is the last time a controller has gone down in price?

When is the last time a controller had a screen? And was bundled with a system, and other controllers couldn't be purchased (in the US).

Exactly.  It'd have to be some very enticing gameplay to get people to shell out the cash for both game and controller, bundled or not.  Especially since there would be no guarantee other games would ever support 2 gamepads.   It's not like Nintendo ever mandated developers (even their own) to include such things.

Wii Play is a poor example because it was a $10 game bundled with a controller that you needed for virtually any game (game was only worth $10).  Considering even the Wii Sports required a second controller, buying one was a sure value, paying an extra $10 for a game? Why not?

Wii Fit is a better example, as you were paying extra to get a balance board for that game alone.  However Wii Fit had very enticing gameplay considering there's a huge amount of people who want to be in better shape.  It's a multi-billion dollar industry.

If Nintendo can tap into something similar to push two gamepad controls, then absolutely, it'll sell.  

How about an educational fitness game for my lazy and dumb countrymen?