That procedure is pretty accurate
Here are the steps we mostly use
0) make a backup copy of your codebase and database!
1) shutdown AOLserver
2) cvs update to openacs-5-5-0-final or merge openacs-5-5-0-final code into your local install, if you have made changes.
3) start aolserver
4) Go to /acs-admin/install/ and click "Upgrade Your System" in "Install from local file system"
5) Select all of the packages you want to upgrade and proceed
6) After upgrade is complete, restart the server as indicated.
OR
4) go to /acs-admin/apm/ and click Install Packages.
5) Check off all the packages marked for upgrade.
6) Wait, then when it is done, restart AOLserver.
The second method let's you see what SQL upgrade scripts will be run etc.