Even the old-format Office files aren't fully supported. Only a portion of PowerPoint's transitions and text effects are available, although the ones that aren't tend to degrade gracefully. How Writer handles complex Word documents can be unpredictable, to say the least, particularly when it comes to fonts. Calc has done an admirable job of supporting basic Excel macros, but not all capabilities are available there either (and it might be unreasonable to expect full compatibility). Unfortunately, LibreOffice does not appear to have done much of anything to improve on OpenOffice.org in these areas.
Still, the similarity between the two suites is overwhelmingly positive when you consider that LibreOffice announced its first stable release in late January. I found no difference between the two offerings either in performance or stability. Neither crashed on me, even when handling documents designed to put productivity apps through the wringer.
New features in LibreOffice What LibreOffice does bring to the table are mostly small, incremental improvements to the functionality of OpenOffice.org. For example, LibreOffice Calc ships with a new set of default key bindings that should be more familiar to users accustomed to Excel or other spreadsheets. Writer includes a new dialog box that makes it easier to format document title pages. And while Microsoft Office support hasn't much improved, LibreOffice does a better job than OpenOffice.org at handling Microsoft Works, Lotus Word Pro, and WordPerfect documents. Various bugs have been fixed, as well.
Perhaps the most significant new feature found in LibreOffice is support for Scalable Vector Graphics (SVG) files in Writer, Impress, and Draw. SVG is an open standard for vector-based graphics that can be exported from many popular drawing applications, including Adobe Illustrator, Microsoft Visio, and many CAD programs.
There's a check box in LibreOffice's options to enable "experimental features." Oddly enough, even with this checked, several new improvements mentioned on the LibreOffice website don't show up in the Windows version. The site mentions that LibreOffice can save OpenDocument files as "flat XML" to make it easier to manipulate the documents using XSLT transforms, but that option doesn't appear in the Save As dialog box on Windows. Also, certain new UI elements, such as radio boxes next to complex menu items, don't appear in the Windows version of the suite. It seems most of the new development for LibreOffice is being done on Linux, with Windows as only a secondary platform.
Which open source office suite is for you? Ultimately, for many customers the decision to use either suite will depend on the extent to which they are wedded to Microsoft Office file formats. Customers who maintain a large number of complex Office documents may find a wholesale migration unworkable. Otherwise, the choice between OpenOffice.org and LibreOffice weighs largely on two factors: support and future development.