Dame Judi hasn't read the script yet, right? Since most of the studio work will be done in the Barrandov Studios, Prague, chances are that they'll shoot her London office scenes there as well. As for M in the Bahamas... maybe M shows up at Bond's post-torture sickbed instead of Mathis- maybe it's her having the whole 'good and evil' discussion with 007, that figures so prominently in the novel. From a screenwriter's perspective, overseeing the bigger story arc of the Craig-Bond films, it would make sense to have M saying 'Don't let me down and become human yourself, we would lose such a wonderful machine', instead of the supporting character of Mathis. Let's face it, Mathis does not really stand a chance of becoming a recurring character in the movies (I even doubt if he's in CR at all, they'll probably just use Felix), and stating the professional relationship between the new Bond and M is much more important at this stage. It also condenses the story. Just speculating of course, but I can see it happen this way.

Some interesting points there, Lounge Lizard. Yeah, I can also see it happening that way - and M zipping about all over the globe is very much in keeping with the Eon tradition, as opposed to the Fleming novels (not 100% on this, but I don't think M ever turns up in the field in Fleming).
Funnily enough, I thought I'd be appalled by news of a Dench return, but I'm not. Yes, she's getting on a bit - but it's called
acting. Yep, it's odd from a continuity point of view, but, hey, we can (as I think someone has pointed out here on CBn) just pretend that the same actress is playing a different M this time round. Yes, I'm not exactly a huge fan of Dench as M, but, well, I'll just have to get over it.
But I agree with Streetworker that a BOND BEGINS-type origin story reboot could seem old hat a year from now. Heck, it looks a bit old hat
now. That's my only "worry" with CASINO ROYALE - well, along with the possibility that the critics will give it a lot of flack for "ripping off" Batman (and Bourne). Otherwise, I still have a lot of faith in the people behind CR, and am confident that it will be a splendid film.