Here's a presentation to Congress by Molycorp, the company referenced in the article as the owner of the Californian mine (the largest rare-earth metal mine outside China): http://www.molycorp.com/pdf/MMCEMARCH09.pdf

Two observations from the presentation:

a) it is an interesting example of how to lobby for government funding, and

b) looking at the hybrid vehicle supply chain figure, it is startling how dependent the future of clean energy is on magnets which are made from rare-earth metals: magnets play a big role conversion of mechanical energy to electrical energy - wind, hydro, wave turbines require magnets, and vice versa (permanent magnet motors for hybrids, electric vehicles etc.)