So it's basically the side-punch from Double Dash!!, presumably usable multiple times. Interesting... I guess a Cape Feather reboot'd be kind of pointless what with the hang-glider system.
EDIT: I'm still curious as to what the distribution of retro courses will be. Thus far, 1 from SNES (a Mario Circuit), 2 from N64 (Kalimari Desert + Luigi Raceway), 4 from DS (Waluigi Pinball, Airship Fortress, Luigi's Mansion, DK Pass), and 1 from Wii (Maple Treeway) have been shown in various screenshots and videos. I guess that 2-2-2-2-4-4 (in order of release) is still a possibility, but I hope that N64 gets more representation than that, and don't think Wii needs 4 as badly. I'd love to see one retro cup per game, but I don't think Nintendo would break the 4-cup mold for that.