AbiSource  has announced the release of a developmental version of its popular and free cross-platform word processing application, AbiWord. Version 2.9.1 represents the first glimpse of AbiWord’s journey towards a major new stable release, which is set to be version 3.0.

AbiWord 2.9.1 includes a number of notable new features – including full Unicode support in Windows (accompanied by improved localization), support for paragraph borders and shading, and an experimental EPUB plug-in, enabling users to create eBooks from existing documents in AbiWord quickly and easily.

The new release also sees the Collaboration plug-in become compatible with the free Telepathy collaboration service, allowing multiple users to work on documents simultaneously in AbiWord. Under-the-hood changes include full support for 64-bit versions of Windows, although an actual 64-bit installer won’t be available until a future release. RDF support has also been added to OpenOffice (.obt) and AbiWord (.abw) files.

The new release – AbiWord’s first major new update since version 2.8 was released in October 2009 – also sees AbiSource restart development on the Mac OS X build of AbiWord, which had stalled with the release of version 2.45. Although no public download of AbiWord 2.9.1 for Mac is currently available, AbiSource has provided a screenshot of the new version in action on its website.

AbiWord 2.9.1 is available as a freeware download for PCs running Windows 2000 or later, or Linux. It’s considered an unstable release for testing purposes only, and not for general consumption. Instead, casual and everyday users are recommended to install and use the latest stable release – AbiWord 2.8.6 – instead.