It's true. The total of storage on S3 equalizes as time goes on. After a couple of days of not uploading my total stored increased since, I'm guessing, the duration stored over amount stored increased. I'll have to wait until the end of the billing cycle to see if there is a 1:1 parity.

Plus I hear that automatic back ups are in the near future for JungleDisk. That way I won't have to second guess by rsync logs.