But I don't see why they would change voices and faces of the same guy, and keep calling him James Bond. For me, the other way round makes a bit more sense.
We've now officially seen new Qs and Ms introduced. I think even Brosnan made a reference to the "old M" when Judi Dench appeared. So why not have the same thing happen with Bonds.
And the Tracy thing... I always liked to think that for example Moore-Bond visited the grave to trick Blofeld into appearing in For Your Eyes Only. That's exactly the purpose of the "Bond identity" (lol). Blofeld didn't know it was a new James Bond, and fell for it.