The Omni Group has released a beta version of OmniOutliner 2.2. OmniOutliner is a Cocoa based list creator designed for making lists and outlines in OS X. The beta release features XML support and stylesheet tranformations. According to The Omni Group:
The Omni Group today released a beta of OmniOutliner 2.2. The new version of the popular Mac OS X outlining tool adds XML export, which allows users to present outlines in many new formats through XSLT (a language for transforming XML documents into other types of documents).
Now OmniOutliner users can use a stylesheet to transform a document into HTML that Word can interpret as an outline. Stylesheets can be created to generate other formats, such as TeX documents.
You can find more information about the OmniOutliner beta release at the Omni Group Web site. OmniOutliner is available for US$29.95.