SofS for Defence had some interesting things to say on on the matter during Sundays Politics Show. It's on the iPlayer if you want to have a look.
In a nutshell he said that our pensions were not going to be touched because of the unique nature of the job we do and the effect it would have on recruitment and retention.
I suspect that some very good work has been done behind the scenes to pave the way for that statement.
Whether he keeps this promise in the face of the Govt's Public Sector Pensions Commission remains to be seen.