Good that others like the idea, another advantage would be that we could save building before a new update is released, so we may prevent losing our creations and share them with others. (Or Steamworkshop implementation?) I think i can remember Red already planned something like this blueprint thing but why not doing a basic functional implementation in this lua script.
A good server admin does create backups before upgrading. A better server admin set up frequent backups, too. However, with the new HTTP method, I surely could see a central repository of serialized data... however such feature is really not ready to get implemented, yet.
Edit: a crazy idea would be to add an undo feature...