Wired has the scoop on the latest advances in artificial diamonds. Given the current situation in Africa, I found this little bit interesting:

Clever marketing may bring buyers around to manufactured diamonds. After all, there's no chance that they are so-called blood diamonds - stones sold by African rebels to fund wars and revolutions. And they aren't under the thumb of an international cartel accused of buying off foreign governments, despoiling the environment, flouting antimonopoly laws, and exploiting mine workers.

As the article points out, the new diamond age may indeed be at hand, and it will have implications far beyond cheaper engagement rings.