Havening an option to take a snapshot of a table would be vary useful in production.
What I would like to see this option do is do a merge of all the data into one or more files stored in the same folder on the dfs. This way we could save data in case of a software bug in hadoop or user code.
The other advantage would be to be able to export a table to multi locations. Say I had a read_only table that must be online. I could take a snapshot of it when needed and export it to a separate data center and have it loaded there and then i would have it online at multi data centers for load balancing and failover.
I understand that hadoop takes the need out of havening backup to protect from failed servers, but this does not protect use from software bugs that might delete or alter data in ways we did not plan. We should have a way we can roll back a dataset.