At the moment, these are little more than optional player characters, which occasionally pop up in minigame collections. The MiiVerse redefines them as your personal online avatar, tied to a persistent account across an all-encompassing social network. To put it another way, it's probably not a good idea to make your Mii look like Hitler anymore. Like Xbox Live or the PlayStation Network, MiiVerse will enable you to send messages to your friends.
However, it goes beyond that, giving you the option to send images, videos or even screenshots of Wii U games. There will also be a Twitter-style social media element, so you can discuss games with the community or recommend them to the rest of the MiiVerse. While MiiVerse appears to be based on a number of existing systems, it's a first for Nintendo, and given their relative inexperience in this area, probably a bit of a gamble too.
The first game we've seen to take advantage of MiiVerse is the ridiculously exciting ZombiU. Leaked screenshots - are there any other kind? - revealed a pop-up message in the corner of the screen, seemingly notifying the player that a fellow zombie-hunting friend had lost a fight with the undead, and become an infected as a result.
Presumably, they would then be able to hunt the other player down and mercifully dispatch them, looting their corpse afterwards. In a nod to the excellent Dark Souls, players can also leave symbolic messages, either as a warning or part of a grisly prank.
This sort of 'asynchronous' multiplayer is all the rage these days, and it could well become one of Wii U's defining features. If there's one thing to take away from this current generation it's the power of connectivity, and Nintendo are wise to base so much around the concept.
When it comes to another aspect of the modern game market, however, the company has proven slightly stuck in their ways. Whether it's on PC or consoles, digital game sales have taken off in a huge way, and for the past few years Wii and 3DS have been left firmly behind. Wii got off to a good start, filling its virtual shelves with the best titles plundered from Nintendo's classic back catalogue, but the Wii Shop soon ran out of steam. 3DS, meanwhile, has a handful of great titles, but if you hop online now you will be greeted by a trickle of old GameBoy games, with no rhyme or reason to their re-release.
Ninty has just started experimenting with digital versions of retail titles, such as New Super Mario Bros 2. Only, in a fit of commercial madness, they've released it at the RRP of £40 - roughly £10 more than the boxed version is currently selling for. Sony is equally to blame here, of course, leading us to believe it's not quite Nintendo's fault, but it's an astonishing situation nonetheless.
The answer here is to simply copy Steam, the store/platform that's near-monopolised the PC space over the last few years. Steam's regular insane deals have helped to prepare an entire generation of PC gamers for the inevitable download-only future. Copy the Steam model, by offering worthwhile sales on digital titles, and gamers will be flocking to the eShop in droves.