I'm not sure if this is the right way to ask this question, but here's basically what i'd like to do:

1.) Push a changeset to a site in IIS.
2.) Don't interrupt the users.
3.) Be able to roll back effortlessly.

So, there are a few things that I know have to happen:

1.) Out of Proc session - handled
2.) Out of Proc cache - handled

So the questions that remain:
1.) How do i keep from interrupting the users? If i just upload the files to bin, the app recycles and takes 10+ seconds to come back online
2.) How do i roll back effortlessly?

I was thinking a possible solution would be to have two sites set up in IIS, one public and one private. Uploads go to private and get warmed up. After warmup, the sites are swapped. A rollback only entails swapping to private without an upload.

This seems sound in theory, but Im not sure of the mechanics. Any ideas?