As the battle for lowest-dollar WordPress hosting rages on I think we'll be seeing more and more services that that meet an important need (backups in this case) while doing the crunching offsite. If you're on a cheap hosting plan without enough cpu or memory to export your own database (which i see daily) this looks like a pretty sweet solution.

Props to iThemes for putting what looks like a serious amount of work into it.

Josh - can you share what will be available for incremental restores? How often are backups created and at what increments can an admin roll the site back? Are you taking that route?