this quote from E3, but as far as we can tell, he's just happy that Halo 4 is returning the player to Master Chief's head. He says he wants to make sure that the new game "lives up to what I think gamers fell in love with," and for him, that means being the Chief again.
Spencer says Halo Reach "made more sense to you if you were a Halo fan. If you were new to Xbox 360, 360 is where you started playing on Xbox, you understood what Halo 3 was. ODST and Reach, maybe you weren't as centered." So, newcomers want -- and expect -- to play as the Chief, whereas fans of the franchise were fine with something new.
At any rate, Spencer's just trying to make it clear that Master Chief is coming back, in both the anniversary remake of Combat Evolved, and Halo 4 next year. Why couldn't you just say that, Phil?