Storage-as-a-Service is relatively new. Today the main value proposition is as a cloud target for on-premise deployments of backup and archiving software. If you have a need to retain data for extended periods of time (1 year plus in most cases) tape is still the more cost effective option given it's low capital acquisition cost and removability. If you have long term data retention needs and you want to eliminate tape, that's where a cloud storage target comes in. Electronically vault that data to a storage-as-service provider who can store that data at cents per GB. You just can't beat the economies of scale these providers are able to achieve.
If you're a small business and you don't have the staff to implement and manage a backup solution or if you're an enterprise and you're looking for a PC backup or a remote office backup solution, I think it's worthwhile to compare the three year total cost of ownership of an on-premise solution versus backup-as-a-service.
Today, HP announced that they will be acquiring the startup cluster file storage software firm IBRIX in a deal with few disclosed details. Congrats to HP for making another interesting acquisition in the clustered storage space, following their Feb. 2007 acquisition of Polyserve and their October 2008 acquisition of Lefthand. IBRIX makes software that allows users to cluster many nodes of storage (either industry standard servers or iSCSI/FC SAN arrays) for use in high performance global namespace file storage.IBRIX’s customer base includes some 175 firms, generally in the high performance compute (HPC), video rendering/animation, and oil and gas exploration spaces.