[aidos]

That is good news. I too wrote a sync layer to sit above boto for a previous project. My use-case is a little different in that I sync from S3 to RackspaceCloud as a backup. I just use file name (object name) as the key because I know that files never change (though are added and removed). I create a complete object listing of S3 and a complete object listing of CF, diff and then sync.

One disappointing issue is that the listing process on CF is a magnitude faster than S3.

    CF: real	2m7.628s
    S3: real	14m15.680s

Keep in mind that this is all being run from an EC2 box, so really, S3 should win hands down.