Are there any practicing professionals (or students who are willing to qualify themselves by citing references) out there who have an opinion on the use of olanzapine/fluoxetine combination treatment for bipolar disorder?

Symbyax (olanzapine + fluoxetine) was recently released, presumably for long term maintenance of bipolar disorder. But, I can find no evidence that olanzapine has been shown useful for anything more than treatment of acute manic episodes. I have checked PubMed, and Lilly's Symbyax website.