Thanks, Todd! We did a demo with our customer, and it looks like they will buy. I found out that the backup deduplication product (aka thin backups?) they plan to use has a folder hierarchy of some sort, so they won't have millions of files in a single folder. It's really a good idea that you guys are using XFS, I think (although ZFS--with deduplication hooks--would rock).
They are a Windows shop, so they will use SMB. Does the NFS daemon count affect SMB?
Well, primary storage dedup might require very low latency access, ala solid-state drives, in order to piece together all the chunks of the files on the fly. So, although it uses less storage, the storage it does use would be much more expensive. How well does DSS work with solid-state drives?