Uh, perhaps you need to do a bit more looking at the website :-)
http://www.omnigroup.com/products/om...iner/features/ in the Export Options section gives some details. The video on Printing and Exporting at
http://www.omnigroup.com/products/omnioutliner/videos/ gives more details. The manual can be downloaded from the link on the right side of the product overview page. Best of all, there's that bright green link up top that says "14 day trial" (it's free, and can be extended by emailing or calling Omni). If you get the OmniOutliner Professional variant, the Extras page has a number of plugins you can install to export to additional file formats.