I've talked before about how if you really wanted to share an accomplishment on the Wii U, it was as simple as screen-shotting whatever you did and posting it to Miiverse. Which you can indeed do! But now that the Wii U is actually in our filthy little hands, a new feature has shown itself: tags.
Look at that right there. Only New Super Mario Bros U and Nintendo Land use it so far, being the only titles that actually feature full Miiverse integration. But the idea is that when you post to Miiverse via an in-game prompt, the game can tag your post with a little green sentence. Much of this so far is just adding a scope to your comment, like the name of a stage in NSMBU or the name of the minigame in Nintendo Land. But the game can also add tags that are based upon events. I got prompts to post to Miiverse in NSMBU when I first beat the game, and again when I got all five save-file stars, and posting right then and there added unique tags to my posts. Had I not chosen to post I'da been outta luck and never had the option to share the tag again, but that's just a game-specific implementation quirk.
So what's so great about a tagged Miiverse post? The tag is added by the game itself, which means it's only there when you actually do something, adding credibility to your post. And you can tap a tag to see every single other person on Miiverse who also posted with it, along with said posts. A mini-community of sweet dudes!
While NSMBU's posting style clearly isn't designed to try and emulate traditional achievement systems with its "post now or it's gone forever" method, other games could easily just add "post" buttons to your in-game accomplishment list, allowing you to share any of your cheevs as a tag, and draw some dumb crap along with them. And like with screenshot-sharing, you only choose to share those you actually give a damn about. Or all of them, whatever!
Just a neat little deet from my time on the street. Meat.
Check back tomorrow for another neat Wii U secret!