Apple today removed the AppleWorks 6.1 updater from the Mac OS X software update page with this note:
Coming soon. Check back for an updated version of the AppleWorks 6.1 preview for Mac OS X.
The AppleWorks 6.1 update for Mac OS X was posted around 12:01 am Saturday morning with updates of iTunes and iMovie. No reason has been posted for the hasty removal so I would recommend that you refrain from using AW 6.1 under 10.0 for mission critical use until an explanation or new version is posted.