Re: Time between QoS and Skyfall (Potential Spoilers)
What a great thread! This question has been playfully ruminating in my mind since I saw the movie - particularly where it falls among the other Bond movies.
We know without a doubt that the Craig films were a pseudo reboot. Not an absolutely explicit one, but we were warned that past continuity would not be absolutely secure.
As my friend Kev says, you really have to enjoy the gambit of movies with a "squinty eye." He means that there is no way for continuity to work at this point, so just sit back and enjoy without over thinking things.
To be honest, I first questioned the blatant continuity problems that I thought were avoidable. Why cast Dench? But I learned to really enjoy her performance. So I'll use that squinty eye to imagine the GE M is not the same woman.
Why is he using a P99 in CR? Squinty eye.
Perhaps someday, we will be treated to a "reboot" that is a period piece. Set in the 60s, at the height of the Cold War, smack in the middle of the Connery time period. That would be really cool. But short of this, no contemporary Bond scenario is going to be 100% continuous. For Heaven's sake, Craig was born 6 years after Dr. No was in theaters. Geopolitically, at some point, some major Bond plots do not work.
With all that said, along with my squinty eye, I still think it's fun (and possible) to create a timeline that works. If I were ordering the Bond movies, I'd probably list them like this:
OHMSS* (these two are hopeless together)
YOLT* (and somewhat interchangeable. I don't like that Bond wouldn't seek revenge in YOLT but it makes more sense that Blofeld's line introducing himself for the first time was "sarcasm" Blofeld not recognizing him in OHMSS)
GE Pre title sequence