According to a dude that knows a dude, the Wii U controller might make itself into an e-reader. Since we have already seen speculation that the Wii U eShop might offer more than just games, this actually seems fairly reasonable. The 3DS might in fact share this service in the future as well.
It seems like another market that Nintendo may be trying to find a way into. With the various Android, Apple, and Kindle e-readers already available, the market certainly boasts some stiff competition. Now if only Nintendo would comment on rumor and speculation. I guess we will all have to wait until E3.