Some copy pasta from the newsletter:

50 GB Free Personal Backups

As previously written about, your web space is only intended for your websites andnot for personal backups. Now every customer is offered 50 GB of storage for backups. The only caveat is, it will be hosted on a separate server, under a separate user account and DreamHost will not backup your backups. If 50 GB is not enough for you, extra space is only $0.10/month per GB.