Very silly story in the Mail - shock, horror, the head of MI6's wife is on facebook!
There's very little revealed in the story that wasn't in the press-release-driven reports when his appointment was announced.
The head of MI6 is not a secret agent. He is a government administrator.
Secrecy used to surround the intelligence service, but that's not because it was intelligence, it was because the British government was secretive about everything. There was a move to more openness under the Major government, and the government is now genuinely slightly more open than before.