[rdiff-backup-users] limited daily backups

[Duke]

If I were to use rdiff-backup to make daily backups, keeping a maximum
of 7 days worth of backups, how is the "base" backup updated?

For example, my first backup is made on the 10th - so that backup has
all the files in their entirety.  On the 11th through 16th only minor
changes are made and saved as incremental backups.  So on the 17th, the
backup from the 10th is updated with the changes from the 11th and then
deleted.

How does rdiff-backup handle this?  What I'd expect is that the changes
from the 11th are merged with the backup from the 10th, which would then
happen on a daily basis as the 11th merges with the 12th and so on.

Is that what happens?

I've been wanting to setup a backup system for quite a while, and I
don't really need more than 7 days worth.  I'd like to burn the weekly
archive to CD as well.

Thanks,

    -- Matt.