New-file-storage stores directly in the operating system's filesystem so is more appropriate for streaming large files than storing them in the database. This complicates the backup process slightly, though.
We do have a LOB interface in the driver but it's not terribly efficient. We avoid Postgres LOBs because until recently they weren't dumpable by pg_dump - my driver solution is slower but allowed for consistent data dumps back when PG couldn't do it with LOBs.
PG 7.2 will have a real BLOB similar to what you see in other dbs but that's a good six months out...
Restricting users? Look for the filter that implements the parameter RestrictEntireServer (or something like that). You can use that as a template for a filter you set up for specific paths, i.e. "/new-file-storage/*"
User registration can be configured via the config file to require admin approval, to require e-mail confirmation, etc.
