I guess the main problem with SPECTRE is that the majority would not know the word ("revoke" anyone?) and would not know about Blofeld´s connection to it either.
They will have to choose a title that a world wide audience will be able to understand... and say at the B.O.
Quantum of Solace? Not saying Spectre, SPECTRE, or however it could possibly be written, should be used, but it's an easier word for the majority of audience to understand than QoS.
For a title, I would rather something a little less spoilerific.