ReynardFox: That is not something Nintendo would do...
You sure? I've heard the license/eula for the DS/3DS was anything you put through the system belonged to nintendo... If it belongs to nintendo, why wouldn't they use it? They've re-purposed and reused old code and characters before.
Besides, they are already charging a huge sum for anyone to use their assets on Youtube from their own personality, content, or gameplay...
I'll be pessimistic until they start making smart decisions.
http://www.nintendo.com/consumer/info/en_na/docs.jsp
User Content
You own your User Content. But by entering into this Agreement you grant to Nintendo a worldwide, royalty-free, irrevocable, perpetual, non-exclusive, and sublicenseable license to use, reproduce, modify, adapt, publish, translate, distribute, perform, and display User Content that you post or provide in whole or in part and to incorporate your User Content in other works, in any form, media or technology now known or later developed, including for promotional or marketing purposes.
edit: Sublicensed, but it's about the same...