According to Atsushi Inaba, producer on the Platinum Games side, has stated that the Playstation 3 is the lead platform that they are developing on. This comes after the making of video debuted and footage of the 360 version being played was shown. People speculated that this meant that the Xbox was the lead console.
Inaba cleared everything up today via Twitter. He stated that when they worked on Bayonetta, the 360 was their lead platform and the other version was handled externally. Starting with Vanquish they worked on both platforms equally with PS3 being the lead platform and the engine being an in-house engine.
He finished by saying that he reason we saw an Xbox 360 controller is because that’s what they use to control the game on the PC they use for cross platform development. The Xbox 360 controller is the only official option here. All of this is pretty confusing but those who were up in arms about the sight of a 360 controller can rest assured that the lead platform is indeed the PS3.