From L.A. Times (http://articles.latimes.com/2011/jan/08/health/la-he-mindfulness-20110109):
Hofmann and colleagues burnished the scientific credentials of mindfulness therapy with a review article in the April issue of the Journal of Consulting and Clinical Psychology. After combining results of 39 previous studies involving 1,140 patients, the researchers concluded that mindfulness therapy was effective for relieving anxiety and improving mood.
The treatment seemed to help ease the mental stress of people recovering from cancer and other serious illnesses, but it had the strongest benefits for people diagnosed with mood disorders, including generalized anxiety disorder and recurring depression.
Jordan Elliott, a 26-year-old marketer for a New York publishing company, said mindfulness training had helped pushed his once-disabling anxiety — about work, the weather, the meaning of life — into the background. “The anxiety is still there, but it’s not as bad as it was,” he said.
Full research available on http://www.mindfulnessblog.nl/images/pdf/Hofmann_2010_MBT_anxiety_depression_review_metaanalyse.pdf