No one is copying Nintendo here, anyway. The iPad and other tablets are more of a source of inspiration here than anything, given their enormous popularity as of late. I mean, unless you believe Microsoft only started considering their controller options within the past year, or totally changed it post-June 2011, but those are both unlikely scenarios.
I don't see a problem with a screen in the controller. The WiiU's controller looks fine, and it's reportedly very light and comfortable to hold. It's not as though you're getting a touch screen interface only.
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"When I was a young man, I had liberty, but I did not see it. I had time, but I did not know it."