Yes, it is.

Table storage has multiple replicas and guarantees uptime and availability, but for business continuity reasons you have to be protected from possible failures on your application. Business logic errors can harm the integrity of your data and all Windows Azure Storage replicas will be harmed too. You have to be protected from those scenarios and having a backup plan is necessary.

There is a really nice project available on Codeplex for this purpose: http://tablestoragebackup.codeplex.com/

PK.