the key complaints when Nintendo rolled out Nintendo Network IDs in 2012 was that, despite Nintendo's insistence that they'd built a modern account system that answered everyone's problems, the benefits associated with the new accounts still weren't quite on par with what players had come to expect on PSN, Xbox Live, and even their iOS and Android devices. For one thing, NNIDs offered virtually no support for digital cross-buy, even for games that appeared on multiple platforms like NES Virtual Console games. You couldn't log in on a friend's system and play local multiplayer using your account and your data. And, of course, the most damning issue of all: if you need to replace your Wii U, your NNID doesn't let you simply log back on your new system and access all your old digital games—you had to make a special call to Nintendo tech support.
Nintendo's recently started paving over some of the early issues with NNIDs. You can now unite your eShop balances across both Nintendo 3DS and Wii U by linking your systems to the same NNID. Some games, like
OlliOlli and Mario vs. Donkey Kong: Tipping Stars, have started to support cross-buy. But many of the bolder issues remain unresolved, even today. Thankfully, Nintendo's new account system—the aptly named "Nintendo Account"—seems to be moving in the right direction.