Does Amazon S3 make any sort of guarantees on your data?

Well since the service level agreement states 99.9% uptime of the service, and the service is online data storage this means they shouldn't lose or corrupt your data, and that it should be available. Also their design if it is as described should prevent data loss.

I don't know if I would use it as long term (many years) backup solution, because I don't know that they would be there providing the service in many years. However is it a safe place to put your files off on the internet somewhere, sure. Services designed for backup have better interfaces for regularly backing up your data though.

That said I have to agree with Jim B. Nobody promises not to lose corrupt or damage data.

I'm trying to think of an enforcable guarantee that anyone makes like that. We use Amazon S3 as a backup for our data but we also have two other backups under our DIRECT control.

Here's the breakdown:

1 server holding the original data at the colo facility. 1 backup server (at the colo) mirroring the original. 1 offsite backup server (in case the colo burns down... highly unlikely) 1 offsite backup up to Amazon S3 1 offsite offline backup in a fireproof safe (in case hackers or some other unforseen catastrophe occurs)

At the end of the day the REAL question is... how much data can you afford to lose?

Then plan accordingly. :-)

not that I am aware of. Then again I can't remember the last time I bought a piece of software that was guaranteed not to hose my PC let alone actually run...