FIFA 13 producer Matt Prior talked about the connectivity of friends in the Wii U version of FIFA 13 and had this to say about it:

“A friends tab that’s always there in the front end on the [Wii U GamePad] so you can tap it, you’ve got a list of friends, the friends list from the Wii U console.”

“You can tap an invite to them, or you can tap a message to them. Obviously, touch screen messaging is much better than the 360 Live virtual keyboard where you’re moving it up and down. We really want to connect friends and allow people to game with friends as easily as possible.”

Prior is saying that there will be “a friends tab” on the Wii U Gamepad that you will be able to select so you can see your friend’s list on the Wii U. You will then be able to invite them to play with you or even message them. Prior feels that “touch screen messaging is much better than the 360 Live virtual keyboard.”

Source: mynintendonews.com