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I'm disappointed. If those examples are the best you can come up with you really have to think harder.
In your Smash Bros. example I can only see beginners wanting that feature. Why would a more experienced player need all that info on their controller screen?
I really don't see the benefit from having a lot of info on your screen when playing Smash or Mario Kart either, as it'll only break your concentration if you have to swift focus between the controller screen and the tv.
I truly hope that Nintendo has bigger plans for the WiiU controller than Racing game GPS's or char sheets...otherwise I'm out.
The biggest issue I see is with 4 player local multiplayer Co-op games that makes great use of the tablet screen. That's a fairly limited category though.
This is a bit off-topic perhaps, but the greatest feature of the WiiU controller imo is the ability to make games where one player takes the role of a "Dungeon Master". And if you have two tablets you could make advanced Counter-Op modes in Single player games where a second player takes command of the enemy.
