MBSR is becoming increasingly common in cognitive behavioral therapy as well -- it's interesting (to me) to see how much intersection there is between meditative practice and what cognitive behavioral therapy is discovering. Different paths to the same conclusions.
There are studies that show a strong correlation between meditation and higher levels of happiness and lower levels of stress. These studies are a big part of why meditation is sort of trendy nowadays AFAIK. Googling [meditation study stress] (or whichever claim you're interested in) will yield a number of relevant results.
This article: "Mindfulness-based stress reduction and health benefits. A meta-analysis" http://www.ncbi.nlm.nih.gov/pubmed/15256293 seems to be relevant to your question.
Of course the mere existence of articles does not prove anything. Caution advised :)