Mario hasn't had a good platforming game since Super Mario World and hasn't a good racing game since Double Dash/DS. The formula they've got for him is old and tired and they're not interested in improving it. They're even screwing with Paper Mario now. If they wanted to they could sit down and make a beautiful, HD, hand-drawn 2D Mario with like four characters to choose from with 90+ levels and it would be great but they just don't want to so it has fallen to the LBP guys and indie devs to make them since they just won't anymore. But that's fine, what these guys are doing with the formula I really enjoy.
D: What about Super Mario World 2? Yoshi's Island had great level designs, bosses, etc. I am getting sick of playing New Super Mario Bros., though.. =_= At this rate we'll be seeing Super Mario Galaxy U.
When I was a kid I was really, really excited when I saw it at first since Super Mario World was one of my favourite games EVER! Then I sat down to play it and my excitement dwindled away and only disappointment was left. Then probably 6 years later or something I saw it again, completely forgetting about it, got excited again "A sequel to Super Mario World I've never heard of!?" get it again, play it again, only pain. I think that happened another one or two times. Never again.