Shawnh, pgk: I'm not sure exactly what to say in response to your posts, except to repeat that as far as I can tell, the is about farmed freshwater terrapins, which are not wild, not endangered, and are not marine turtles.
Some fresh water terrapins that are endangered - the very distinctive Chesapeake terrapin (US) is one. There are also endangered Asian terrapin species, and some of these have been exported to China. However, there is no evidence on the web site Scuba_SI posted (nor any of the other sites that I could find) that the turtles that are being sold in China by a Shanghai supermarket chain owned by Tesco are anything other than Pelodiscus sinensis, a common turtle that is widely raised in ponds in China, Vietnam and Thailand for food.
CITES is involved in monitoring China's production, import and export of turtles (marine), tortoises, and terrapins, and apparently there are signs that China is doing a better job of controlling the trade in endangered chelonians, though that's not necessarily saying much. In any case, I think it's unlikely that you or anyone else could ever confuse a farmed terrapin with an oceanic turtle.
There is useful information at:
http://www.itmonline.org/arts/turtles.htm
and
http://www.conservation.org/ImageCache/new...rofiles0503.pdf