No detailed upgrade journal, you really ought to read John Siracusa’s latest novel for that. The only thing that was immediately broken was the URL for this blog, because Leopard switched things over to Apache HTTP Server 2.x and doesn’t move your old configs over.
sudo cp /etc/httpd/users/* /etc/apache2/users
If I have anything to say that you haven’t already read 167 other places, I’ll post it.
Everything is always done for the wrong reasons.