I don't have a WiiU so I don't even knoww what Miiverse is lol
Imagine needing a certain piece of a furniture set for example. You press home -> go to Miiverse -> the AC:NL community board -> write a message asking for a trade -> go back into your game and wait -> get notified of a reply -> share FC's to do the trade.
This is exactly what I was thinking. Although there is the fact that not everybody has found this forum or any other like this and Miiverse could be a common place to share things about this game for everybody. Also, there isn't always a computer available when you're playing on a handheld and I personally don't like searching the web with my 3ds.I don't see the difference between the Miiverse being used for Animal Crossing and the use of online message boards. Wouldn't it be easier to just search for it on a computer?
To add to this, since the Wii U has easy friend requests through Miiverse and no friend codes, it's even better.
Honestly, it kind of replaces the need for forums like TBT for trading items.