Heh, ah memories, I can somewhat relate. I was a student in Japan, but spent a bunch of time hanging out with Taiwanese business men in southern China after that. The first block of time I spent there (relatively short) I couldn't speak mandarin at all, and it was pretty miserable experience. The second block of time I spent there, my mandarin had gotten pretty decent, and so I was able to flip everything into a learning experience...from learning words in Chinese like "static IP address" to how to politely refuse a karaoke prostitute my host habitually tried to force on me, those are some life and language experience I didn't get in the classroom =\
If you're an American living abroad, 6 months is the minimum, and you should really stay at least 9 months. Why? Language is everything.
Seriously - in most places sufficiently different from the US to be interesting, language will be your first and most formidable barrier, on the other side of which lies one of the most satisfying experiences you've ever had. It'll take 6 months after you arrive to cross the language barrier. Your life will rock afterward, so plan at least 3 months (more is better) to enjoy the awesome part.
Example: I noticed I'd crossed the barrier when I managed to land a gig drumming for a Tokyo funk band, and I was the only Gaijin in the bar at our first gig). From then on, life in Japan was awesome. I could call up and organize scuba diving trips in obscure bays on my own, I could pick up Japanese girls using only Japanese (try that!)
