Can I use MT-NewsWatcher on more than one Mac and have it somehow magically synchronize my user group lists?
Yes. Here’s two ways to do this: The first way is to use a personal MT-NewsWatcher floppy disk which contains your prefs file and user group list file, and carry the floppy around with you. The second way is to store your user group list file as a .newsrc file on a remote host and use the MT-NewsWatcher feature which fetches and puts back the .newsrc file for you. See the chapter on Sharing Newsrc Files for details.