I gave OpenOffice.org 2.0
a spin today; I installed it, started up Writer, imported a >6MB Word document spanning well over 100 pages with lots of graphical content, edited huge chunks of it (including vast modifications, new pages, internal links, cuts and pastes from various sources etc.) and found it to be mostly superiour to Microsoft Word 2003
For starters, the menus make a hell of a lot more sense than the obfuscated Word system of nested option dialogs. It was a lot easier to find stuff in the menus, and - much more importantly - everything worked from square one. I hardly had to touch the options (only to reassign Ctrl+K to "insert hyperlink" - an old habit from my Word days) and I could play the software like a finely tuned piano. I found it superiour to Word in many subtle ways: for example, the Navigator (F5 by default) turned out to be invaluable for said document (which is tightly hierarchical and very long and complex); linking was almost as good, requiring just one more keypress than Word for internal links within the document; formatting and reformatting was made a lot easier with HTML-like formatting options and built-in keybindings (such as Ctrl+0 for default formatting, which I found invaluable) and the whole shebang was rock-stable. Now that's what I call open source done right!
I did have a few gripes, obviously. For starters, I couldn't find a "Navigate Back" button anywhere (in Word I remapped it to Ctrl+-, in lieu of Visual Studio 2003) which I sourly miss. Believe it or not, the only other gripe I have is with the loading/saving system: the loading/saving times are considerably higher than Word, particularly for imported/exported documents (i.e. loading or saving a Word-format doc file). Word appears to implement some sort of delta-save mechanism, because when editing the same document with Word subsequent saves via Ctrl+S (which I do about twice a minute due to paranoia, same with Visual Studio 2003...) were considerably faster (sometimes 1-2 seconds instead of almost 10). However, remember that this is a huge document we're talking about - I've rarely edited 100-page documents, or even seen them being edited. Not in my profession anyway.
I've yet to give Calc and Impress a spin, but if Writer is anything to go by I expect to be blown away. Until Office 12 comes along I doubt I'll be firing up Word very often.