I don't know where that suspend to disk idea came from, I agree with you on netboot. :-)
There would be some kind of proxy/staging area ofcourse, and all containers (i.e. databases of objects) would be on "always available" servers.
We should just build our own version of Glacier now that we know how.. ;-)
On another note, hopefully more backup vendors will support storing data to these kind of services soon. I know some open source solutions integrate with S3/Swift and I also think CommVault Simpana and Seagate i365 does.