Apple released iWork 09 9.0.1 last Friday with improved support for other file formats as well as stability enhancements. The update included fixes for Keynote, Pages and Numbers.
Keynote 5.0.1 fixed reliability issues when deleting presentation files, copying slides between presentations, and working with transitions and builds. Pages 4.0.1 addressed problems with deleting files, and improved reliability for EndNote X2 and MathType 6 files. Numbers 2.0.1 fixed problems with deleting files, customizing the toolbar, working with charts and certain functions, and importing Microsoft XLSX documents.
The update is free and available via the Software Update application, or as a downloadable installer at the Apple Support Web site.