Smudge,
Maybe one point to consider in reply to your comment ("many current service personnel may shun PPRuNe military on the grounds that its inhabited by old codgers") is this: many cuurent serving personnel read but don't post on PPRuNe because they consider it unwise to do so, and do not want to run the risk of compromising operations or personnel, or starting potentially damaging rumouors. Yes, I know PPRuNe is a rumour network... I certainly never posted when I was in the Service but having left I now feel fairly safe to do so (within limits). That said, it was great to read some of the old stories even if I couldn't/wouldn't reciprocate with current yarns.
Bottom line: I think PPRuNe has the right blend of current and ex-serving members, even if the ex-serving members appear to post more.