Just a heads-up on this one about a problem I just encountered.
: "After upgrading you need to visit this URL to update your DB: http://www.domain.com/forum/install/database_update.php"
Upon running the upgrade on a handful of forums, the script had apparently zero'd the config.php in both the upgraded directories and the backup .old directories it created, thus making PHPBB3 think it was performing a fresh installation and not giving an option to upgrade the currently existing database by following the above instruction.
This may have been an intermittent glitch local to my account (I won't know until Support get back to me) but just in case, make sure you backup your original config.php file and if you receive errors after following the upgrade instructions, upload your config.php overwriting the zero'd one in your new forum directory and then browse to the database upgrade link.
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