We know all the "drill" of migrating a site:
- Put your site on maintenance.
- Backup your database and code
- Disable all your modules (do this with 50+ modules)
- Update your core and modules code
- run update.php
- check for errors in update screen
- activate a module
- run update.php
- check for errors in update screen
- repeat last 3 actions until you have migrated all modules
And then we are not talking about migrating buddylist to friendlist or views 1.x to views 2.x.
