The graphics are significantly worse than Double Dash's (which boggles my mind)


Drugs are bad.
online is severly crippled (no grand prix, no free for all battle mode)
Completely ignoring that it's 12-player online, even has an online battlemode for the first time ever, the new game types in battle mode, ability to check world wide record status, local record status, ranking, downloadable ghost data, and worldwide online events like Time Trials
the trick system doesn't seem to work at all on a regular controller
The trick system was designed for motion controls (just as shake smashes were in Brawl), and were built to show off the Wiimote control scheme. If you don't want to do the tricks, just stick to the carts which don't use them anyway (only the bikes do) and you will be playing classic Mario Kart. The tricks and bikes were added for people willing to try something new (i.e. motion controls).
there is severe slow down in split screen multiplayer (wasn't there on the much better looking Double Dash... WTF?)
Source? Only time slowdown was mentioned was in the IGN preview over a month ago in which they admitted they didn't have the final build. The only review readable online is considered harsh by most people (was an 8 out of 10) and they didn't mention it...
How imaginative the tracks in is your opinion, which you're welcome to. Not sure what the heck the basis for the rest of your post was though.