That doesn't sound too terrible, except for the manual fiddling. That's terrible :)

Start off with a manual process, but, three strikes and then you automate. Especially important and error prone and stressful things like making a release and deploying it to an environment (release and deployment are two different things). It should be as effortless as running a script with some config options.

We use Templare Toolkit to generate config files (e.g. httpd.conf) from templates, with current release and deployment values.

You should have a process in place (and by process I mean a checklist of what needs to be done, and scripts to automate anything automatable), maybe on a Wiki page. There are probably non technical steps here: telling people before and after the upgrade, assembling a set of release notes, updating the list of what's deployed where (unless you automated that too).

The only thing in your description that sounds odd is exporting the working copy. Wouldn't it be better to base the release of a clean check out to a temp directory, so you're 100% certain it contains what's in the repo and nothing else?

/J