Personally the 3ds version might be the only version I care about. Come on it's a portable smash bros, that in it's self is amazing. I was actually quite afraid that the 3ds version would be scrapped early on. Although brawl can be improved upon, I just sort of see the wii u version as another brawl. I don't know about everybody else but I like to have the game right in my face, it feels more personal, and I prefer to lay down well playing video games. I like the idea that I can take it around with me.
I loved mario kart 7, but never really got into the wii version. The main reason I was excited about brawl though was the online, and that sucked, so yes, I probably will get the wii u version eventually. Also I hope this new version is more combo friendly than brawl was, seemed like I could never quite dominate in brawl no matter how good I got.