Like I said somewhere in the "DSi or PSP?" topic, the Mario vs. Donkey Kong series is dead to me. I thoroughly enjoyed the first one. I enjoyed it so much, that I completed each and every stage, taking several tries to get gold stars and unlock every stage (which I eventually did). Mario vs. Donkey Kong 2 is the game that officially ruined the series, in my opinion. I'm not saying it was a terrible game or anything, but it just definitely didn't do it for me the same way that the first one and Donkey Kong '94 did.
I don't know why they felt the need to stray so far from the gameplay styles that were established in those games, anyway. What's worse, is the fact that they decided to reuse that exact same formula for the next two games, as well. One other thing the plot seems to get significantly worse after each installment. I know that Mario platformers are never too big on storylines, but the ones in those games are just ridiculous.
Mario Kart 3DS is the only one I'm looking forward to.
I don't really like Paper Mario with the exception of Super Paper Mario and I've never been a Donkey Kong fan. I'm still undecided on Mario Sports Mix.