I've been doing FileMaker work for quite a while but I haven't done much multi-user stuff so I haven't run into this issue before...
With just a single-table solution that has a list view and a form view, I have 2 users looking at the identical list view layouts that show all records in the table. When a change is made by one user (e.g. new record, delete record), that change appears instantaneously to the other user. So far so good. However, if that second does a find so that his found set is less than all records, then changes made by the first user don't show up, at least not until the second user asks to show all records, or performs another find, or closes the file and reopens.