In an update earlier this week, AbiWord introduced several new features, one of which competitors have long had. In AbiWord 2.8.1, you can finally annotate a document. There's also integration with the new Web-based sharing tool called AbiCollab.net. This extends Google Docs-style sharing to AbiWord fans.
Other features have been fixed or introduced, too. Smart Quotes, the curved quotation mark, had been implemented before, but they now work as they do in other word processors. A multipage view has been introduced for examining more than one page of your document simultaneously. For users who need robust graphics support in their word processor, AbiWord 2.8 also natively supports true vector images (SVG) as well as WMF images from Microsoft Word.
Further changes are documented here. If you have a favorite word processor, let us know in the comments below.