Could be me being over optimistc. BUT I see nothing that TOTALLY contradicts the existence of the old films nor does Dench-M seem to stick out.
I quite like the reboot idea, and I think CASINO ROYALE as presented here works best as an origin story. Viewing it as "just another adventure" for Bond ruins all of this film's appeal. This film is about the rookie, arrogant Bond getting broken in, so to speak, and that's important.
And just because of what the review says doesn't mean it's not stated more implicitly in the film that Bond's just entered the service. And note that M states that Bond "celebrates" his Double-O status by attacking the embassy. It seems clear as a reference to his just having received it.
I don't understand why fans are so desperate to jump through tons of hoops just to say, "CASINO ROYALE wasn't a reboot!" It damages the film to try to force it into that framework, rather than accepting it on its own merits.