The only problem with tarsnap is that it uses AWS, or did as of the last time I talked with Colin. I would love to see it move off onto a less personally annoying service, but its service to do with as he pleases.
I know scrypt is awesome, but isn't encrypted traffic still problematic if all traffic is being recorded? If the NSA Rubaiyat has virtually unlimited resources, doesn't tarsnap eventually break down as a safe way to backup data? I'd love to hear Colin chime in.