IGN's Main controller article...
http://cube.ign.com/articles/651/651275p1.html
IGN's newest controller article...
http://cube.ign.com/articles/651/651559p1.html
Due to the backwards compatibility that Nintendo plans to add to the final product, they also decided to make an add-on that will work for the Gamecube games. Pretty nice idea, might I add. As IGN said, the mock-up that THEY (IGN) created is only based on what they were told.
But lets go with a prediction I made up. This has to do with the controller based on looking at it sideways so that the D-Pad is on the left side. Look familiar? Yup. You guessed it. Because of the plans Nintendo has for being able to purchase older games online, you will be able to play any purchase NES games just like you played them when they first came out.