Every time I hear about Thorium I get a "Too good to be true" feeling but I don't know enough about the technology (and there aren't enough good sources about it) for me to make up my mind. This article cites that there are significant development costs for the first reactors and that few nuclear engineers are educated about them, but both of those are easily solvable problems for a smart team. What other negatives do Thorium reactors have?