Having been partying with Sir Richard last night in HK [ :clang: ] it seems he is pretty serious about this. Whether he pulls it off is another matter, but he clearly had the support of his top frequent flyers in the room.
One of his colleagues commented that BA made a big mistake in declaring it "uneconomic" in that they can't really refuse someone else a chance to make it economic since Concorde is in some sense a British national asset. If they had declared it "unsafe" they would have been able to justify scrapping them.