One thing Abiword does not share with its suite-based peers, however, is an appetite for disk space or a Sasquatch-sized memory footprint. Abiword, for example, requires about 19MB of RAM at startup on my Windows XP system, while Writer requires more than 50MB. This doesn't matter much on a dual-core system with 2GB or memory, but it can make a real difference on an older desktop PC or an ultra-portable laptop.
I also find Abiword's user interface to be extremely clean and functional -- the result of thoughtful design decisions as well as the fact that Abiword doesn't need to pack the same functionality into a limited amount of UI space as a suite-based product does.
When you're traveling really light, Abiword runs just fine on a USB drive or other flash memory device. The version available on Portableapps.com (which is compiled especially to run in portable environments) requires only 15MB installed; although the portable version of OpenOffice.org also does a fine job, it requires more than 80MB of storage and is, in my opinion, a bit slower off the mark.
As always, an open-source, small footprint application like Abiword is most useful when you know its limitations. In this case, that list is surprisingly short: Support for annotations is still in the works (and available on development versions of the program), and the Windows version of Abiword lacks Unicode support. Some folks also cite a lack of support for embedded audio/video and an integrated chart-making tool as major shortcomings, although of course that depends entirely upon individual users' needs.
One area where a serious word processing tool cannot afford to fall short is document-format support. Abiword does quite well in this respect: It opened a number of ODF and Microsoft Word (binary DOC format) documents without a hitch, and OpenOffice.org had no problem opening ODF and DOC files created in Abiword.
Currently, Abiword handles its ODF support via a plugin rather than as its native format, and it provides import-only support for OOXML via the same plugin. The use of a plugin is a non-issue for me, since users can still set Abiword to use ODF as the default format once it's installed. In any case, Abiword's involvement in the 2008 Google Summer of Code means that both of these issues, along with support for annotations and full Windows unicode support, are not very far off.
Although Abiword is available for both Windows and Linux, I think it is especially important for Windows users to know about it. There is already a healthy competition among Linux-based business productivity tools, including OpenOffice.org, Abiword, KOffice, and others. On the Windows side, even when people know about OpenOffice.org -- and many business users still do not -- a vast gulf exists between the plus-sized office suites and, at the other extreme, useless toys like Wordpad.
Abiword fills that void for Windows users, and it does so amazingly well. That makes it ideal not as a replacement word processing program, but rather as a useful -- and eventually, indispensable -- addition to any small-business software library.