The funny thing is that I've been in the Army 20 years, and have never been to Korea. Yet, I know a few Korean phrases, just because almost everyone goes there at some point, and things like (and I'm butchering the transliteration of this, Im sure) kom-sa-me-dah have made their way into Soldier vocabulary. So when I read your post, I recognize "ajumma" as a word I've heard people say, but never really knew what it is.
I'm psyched to get over there and start a new job, and to adventure in a new country. Thanks for all the advice, folks.