Nintendo's pushing out version 4.0 of its Wii U system software, and it's bringing a few unexpected -- yet welcome -- changes. Ironically, tweaks to how the hardware handles titles from The Big N's last home console headline the update. Folks taking Wii games for a spin will now be able to do so using just the GamePad's screen, and enjoy Dolby Pro Logic II surround output -- though you'll still need a Wii remote to play. Iwata and Co. have also rolled in an image sharing tool that mirrors the one on the 3DS, which lets gamers share screenshots on Facebook, Tumblr and Twitter. With the fresh code in tow, demos from Nintendo can be downloaded automatically and a variety of USB keyboards are supported, to boot. The box's internet browser also got some attention, as it's been bolstered with the ability to open PDF files and remember user login details for web sites. Check your Wii U for the update or click the source link for the full changelog.