Many government and business email systems are systems are installing screening systems to monitor what kind of email their users are sending, and receiving. The American military has long monitored all the email coming and going to .mil email addresses. These systems, increasingly popular in business and foreign militaries, look for certain words or phrases indicating a message that shouldnt be there. Not just bad language, but unauthorized discussion of secret material or indications of disloyalty. The current terrorism anxiety is making this sort of thing much more common and will increase.