If you own a Wii you'll know that online wasn't a major part of that experience. Things look very different with the Wii U thanks to what Nintendo has called the Miiverse. This collection of tools that appear to provide Twitter and Skype-like functionality are built into the system, so you can access them from anywhere, even if you're playing a game.
The hugely popular Mii characters obviously return, and the Miis of your friends and family will be present on your home screen, gathering around the titles they are playing. The friend code system found in current Nintendo titles will return in some form, but it's said to be easier to use.
Head to page 3 for info on the console's launch games.