Is it just me or are the major news services missing the whole point of the Wikileaks US embassy cables? Sure it's a bit embarrassing for the Yanks that their data all got into the public domain, but I'm sure all the players know these kinds of unflattering accounts are a regular part of diplomacy.
The really important thing here is that if a disgruntled employee with access to this data was able to very easily gather the whole database and leak it to Wikileaks, how many other sources are there leaking it less publicly? There's upwards of three million people who have the appropriate security clearance. Do you think some of them might be financially distressed (given the recent GFC) and be open to a little cash incentive to leak it somewhere else? Or have some other easy method to apply leverage (especially given "Don't ask. Don't tell.") So the question is probably less which intelligence agencies have been regularly receiving this data and more which ones haven't! Of course, their versions wouldn't have had the redactions of personal identifiers and the like that we see in the Wikileaks data.