We've all talked Euro-RoHS to death over the last year. Well, there's still a lot to learn but a lot has been said. Now we have the China RoHS to figure out and unfortunately it is different enough from the European version that complying with one won't necessarily get you into compliance with the other. What's a BGA to do?
Probably the biggest difference is that, starting on June 1, 2006, the European Union prohibited the banned substances, while beginning March 1, 2007, China just requires labeling of the covered substances. I ran across this FAQ article that gives a pretty good overview. Here's another one from the AeA.