Diamonds are associated with romance and marriage - thanks to a successful marketing campaign by De Beers, a South African company.
However, of late, the man made diamonds are getting better and are likely reduce the value of diamond as an investment. A better investment is likely precious metals like gold or silver which have to be mined and cant be manufactured in a laboratory.
As the articles in Chemical Engineering News and the more main stream MSN Money show, the man made diamonds are getting to be more mainstream and less expensive than the mined diamonds. It is conceivable that the price points for diamonds will drop significantly in the next ten - twenty years as man made diamonds get to be more mainstream.