The changes to the site will probably happen this weekend or early this week after all. I have been playing with redirects and the like and have modified a migration script so that permalinks will still get you to the correct page. I just need to write a theme for the new site, and verify whether my changes will keep the feeds working or not. If not, then I will need to figure something out with that.
Just an update, and an explanation for anybody that has noticed anything strange over the last couple of hours.