I kind of want this game, but then kind of don't.
I'm not a big fan of Mario games, but I do find them enjoyable. The thing I find lacking in them is the re-play value: once you've played through all the levels, it kind of gets dull with only the urge to own the last star coin making you want to do it again. The thing I hate the most about this is the fact that it forces you to go through the levels you hate the most over and over again, searching every nook and cranny to find those illusive star coins. Apart from this, there isn't much compelling you to play the game again once you've completed it.
But in this new game, I can imagine it being a lot more fun. With all those coins bouncing around the place begging to be picked up, the experience of re-playing certain levels and taking different routes to see what sort of massive cache of gold disks lies around that unexplored corner will be a much better one. And it will be a lot easier to reach that 99 life milestone that every Mario gamer strives to reach before they can call themselves a pro, meaning that the prospect of taking a possible life-costing risk of jumping to that hard-to-reach platform becomes less scary, with all those extra lives stashed away.
I might buy this game if I wasn't already saving for a Wii U (with accessories), Pikmin 3, NSMBU, Nintendo Land, two Remote Pluses and Nunchucks (maybe three), an eShop and an iTunes voucher, new headphones, and still keep some money aside for whenever Mario Kart Wii U and Super Smash Bros. 4 come out.