That depends on what your definition of snapshot is. If you want *true* snapshots then rdiff-backup is not gonna cut it. It will backup your files just fine (like BackupPC, which is what I use), but it will backup each file one after another and doesn't necessarily give you a true point-in-time snapshot of a filesystem.
I assume he means a snapshot backup. Is that what you meant?
If so, you can roll back with rdiff-backup and BackupPC and you can create point in time backups with rsync backup if you use a branching tree. The branching tree method is easy to use but requires a little skill to setup, the roll back method with rdiff-backup is a little more work to use, but its automatic and very easy to setup up. BackupPC is very easy to use, but requires some work to setup.
If you want backups, NEVER rely on file systems snapshots EVER. A snapshot is not a backup. If you lose the drive(s) or file system you're hosed. A snapshot is a local point in time copy of the filesystem, not a backup.