Apparently, the publisher discovered some last-minute issues with the Wii U and 3DS versions of the game, and were forced to choose between delaying the game or sending it out, bugs and all. Interestingly, they opted for the latter. "Our fans want to play the game and we don't plan to leave our Nintendo fans behind on a game they've been patiently waiting for," the representative informed Joystiq.
While a buggy game is never pleasant to experience, there is some good news for potential buyers. A special promotion will grant customers who already own a Nicalis game (VVVVVV, NightSky, Cave Story, Ikachan or Grinsia) on their 3DS a discount for 1,001 Spikes. These customers can purchase the 3DS version for $9.99 - 33 percent off the usual price of $14.99. And as for those bugs:
"Nintendo has assured us that an update could be issued within a couple of days of release to knock out those bugs," the Nicalis rep said. Hopefully doing so will be easier than navigating the game's insane levels.