Let's not kid here Bayonetta is a niche franchise. Which in turn surprised me when there was such a backlash for the exclusive announcement for the Wii U. The franchise had an extremely low attachment rate from last gen consoles that one would think that PS360 fans really didn't care about the franchise. Well hopefully it will find it's fanbase on the Wii U, just as long as Nintendo markets the game upon release.
First thing Nintendo could do is to provide an incentive for potential Bayo fans to pick up the game. They could do this by bundling a cleaned up (glitches fixed) version of Bayo1 as an eShop download for the first printing of the game(first 60-100K)! This would provide an extra value preposition for people to pick up the game at launch costing Platinum or Nintendo next to nothing. This also could provide additional revenue for Nintendo/Platinum if they sold the game for $15-$20 on the eShop to those who are not willing to pick-up Bayo 2 at launch.
Second, Nintendo must increase awareness for the title. Nintendo, could provide downloadable demo's on eShop and make the game playable on retail kiosks. They could also provide some print ads next to said kiosks to show them there is a new demo available for this EXCLUSIVE GAME!!! Nintendo's marketing team also should utilize social networks like FB, twitter, Mii-Verse etc to reach out to more gamers that may be interested in this franchise. Finally they should do a Nintendo direct which provides adequate time for gamers to get excited over the game.
In all, the game has potential to be a successful core franchise on the Wii U as long as Nintendo provides decent marketing for the game. They could do this by bundling the game with the original Bayo to provide extra-value to potential buyers on the fence of picking the game up on launch. Nintendo needs to use ND, Mii-verse, demo's, and social networks which provide low cost marketing yet provides a diverse reach to many potential consumers. Maybe one should bring this to the attention of Kamiya via twitter and see if Nintendo responds like they should?