Contrary to the glowing media reports of almost magical properties, an FDA advisory panel has essentially concluded that TMS doesn't work. Better said, the NeuroStar machine made by Neuronetics failed to impress them. The two most revealing quotes from a WebMD article:

Perhaps a reasonable person could question whether there has been an effect at all," says Thomas G. Brott, a neurologist from Mayo Medical School in Jacksonville, Fla., and the advisory panel's chairman.

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Diana Zuckerman, Ph.D., president of the National Research Center for Women and Families, told the panel the company's studies did not show the device could help patients. "It's not a statistically significant difference, and it's not a meaningful difference," says Zuckerman, a clinical psychologist and epidemiologist. "Yes, it is safer than ECT, but it doesn't appear to actually work."

Device For Depression Criticized