Not a compliment.
...I'm just someone with an opinion...
Guys.
Let it go.
- Diana Rigg (because she's DIANA FREAKIN' RIGG)
A few years ago (and before Skyfall went into production) there were rumors of Rachel Weisz being the head of Quantum, which I thought would have been interesting. Even without her, I rather hope they do something with Quantum before Craig is done, especially since they spent two films building them up.
As I recall, they busted the guy in South America who was running the scam, the guy who got Vesper killed, and the contacts for the guy who was running the Quantum scheme in the first film. We have no idea if there are more out there, as far as I can recall.
I wouldn't be surprised if they return to Quantum eventually, perhaps even referencing how this or that instance from previous films were connected.
I thought Mr. White was the guy who Bond shot in the legs at the end of CR/start of QOS?