Wii U GamePad battery can maintain almost a 100% charge for around 500 recharges before it starts to decrease to around 70% afterwards. The batteries are also completely replaceable with a simple screwdriver unlike with Apple devices and the PS3 controller.
http://www.destructoid.com/you-can-r...f-238282.phtml
Nintendo of Japan released a teaser image of the eShop's appearance on the Wii U.
http://www.destructoid.com/nintendo-...p-238279.phtml