A word of caution. There have been folks with lots of problems with syncing file in FTM2012. (Read the posts in this forum).
1) You can stick with the old-fashioned upload once a week or month and delete the old file. This will create new urls for everybody in your file.
2) Be overly aggressive in backing up. I have a backup plan that considers a parent, ggp, gggp and ggggp backups that overwrites the file on various media, both in and out of my house. I also have archival backups (ie permanent backups with backup dates in the file names).
Just a word of caution.....
I don't like FTM because if you make it public, people can rip off your work a family at a time; and if you make your file private how useful is it?
I prefer to make a gedcom and upload it to the old Rootsweb tree host called WorldConnect. You can set your own privacy rules, your own gedcom guidelines, the reports there are much better than the anestry trees (although the family page of the ancestry trees is better than WorldConnect).
WorldConnect is here:http://wc.rootsweb.ancestry.com/
Per FMT, there will be no FTM2013. Which is good and bad. It's good because we don't have to shell out another $25 for another "weak" update. But, it's bad because it is an admission on their part that they hadn't come up with enough valuable improvements to the program that they could justify billing us for.