Are you going to leverage cloud as a storage tier?

I tend to do quite a bit of reading in the storage arena, probably more than I should and twitter certainly helps this habit.  Some of the people in storage that I follow, made mention of Marc Farley leaving HP to do something else.  This got me a bit curious about what he might be up to since he has been working in storage for quite some time, I was curious to find out what that might be.

When I did learn where Mr. Farley had landed, I was curious about what this company was all about.  Storsimple creates storage that leverages the cloud (using a number of different partner providers) as a storage tier.  Put simply, things that live on a StorSimple appliance in an organization, get pushed off to the cloud as their slower tier.  The files are deduped and compressed so that as little data as possible gets to go "to the cloud".

I think the idea of leveraging cloud as a storage tier is very interesting, it solves a few problems in that your data is replicated offsite to a well-managed site (assuming Amazon and others are well managed).  This puts a copy of the data elsewhere and allows local storage to be full of "hot" data.  It isn't just StoreSimple doing this, Amazon has a cloud gateway concept and others are sure to follow.

My question to you is this: Have you considered the cloud as a tier in your storage architecture?  And if so, how is it working out?  If not, would you consider shipping in-use data off to the cloud as a tier of storage? Regardless of provider, do you trust the cloud for this type of use, or closer to home, can your bandwidth live up to such a solution?

This is something I plan to discuss internally for sure to see if there is any benefit for my organization.  Just wondering what some of you thought about this idea of cloud-tiering.