Yes, I know MK needs an update, but how?
There is no option anywhere to update anything of the sort.
Switched off, on, launched it from main screen, still stuck on old version.
I have the eShop version of MK8, in case it makes any difference
Maybe it'll just download when it feels like it
FYI, I had this same problem this morning - I quick-launched into MK8, then when I tried to go online it said I needed to go back to the Wii U menu and get a software update. Except... there was no indication of where I was supposed to get the update - e-shop? Download management?
Turns out all I had to do was launch the game from the regular Wii U menu (not the quicklaunch menu), and it automatically started downloading the update. So normally it shouldn't be confusing and should happen automatically, unless you quicklaunch the game and skip the regular menu. EDIT: oh wait, you said you launched it from the main screen. Hmm, don't know what the problem is then.
On the update itself - I like the new mini-map, but having to press the - button to bring it up is inconvenient, because I usually have my fingers on the accelerator almost as soon as the race begins. Though after a race or two it seems to stay there and you don't need to press the button again. Oh, and I"m a bit iffy on the Mercedes designs, but they do make nice engine sounds.