i haven't played it much but from what i did play it is still a solid mario kart game. but not a good as double dash imo.
I really liked the DD version of this game. It was actually a game me and my wife played a lot. The game play was absolutely solid. When I first started playing this version I thought the same thing. The more I play the Wii version, the more I am starting to like it better.
The weird thing is that is gives you a choice between Automatic and Manual. I thought this was shifting (for some reason) - but, it's actually the the turning. If you choose Auto then the turning is a lot easier, but you lose the ability to drift and get power boosts off that. I think the drifting is a HUGE factor in the game. So, after I flipped through the manual I figured that out.