One note about tea house scams. Though, obviously, the kinds of experiences recounted in this thread are simply con games, they are, apparently, modeled on tea samplings (I'm not sure of the Chinese name for this, or a good English translation) that are quite legitimate. As an example, we were most recently in Lijiang in Yunnan Province. The area is famous for its tea and, in particular, one made from fermented tea leaves called "pu'er." While we were visiting one of the World Heritage towns in Lijiang, we experienced such a tea sampling. It cost, if I recall correctly, about 40 RMB (about $5 US) for the two of us. The hostess made many pots of a variety of teas for us to sample, explaining, in detail, the characteristics of each, differences in how the tea is grown, etc. Preparation was in the traditional matter. The hostess spent about 30 minutes with us (and, of course, my wife had to translate for me -- her English wasn't good), it was quite interesting and I learned a lot about tea that I didn't know. Of course, all the teas we sampled were available for purchase, but there was no pressure to buy anything. Nonetheless, we spent a few hundred RMB (perhaps $40 US total) on a range of teas. We've done this at a number of places in China though, admittedly, never in any of the large cities.

My point is that visitors to China should, of course, be on the guard for the tea house scam, but shouldn't automatically dismiss anything having to do with tea as a con game.