I've read the rest of the posts on upgrade/install, but I must be missing something.
I used cpanel/fantastico to install 1.2 in a new sub-domain. new mysql database, etc.
but your dns may not see it yet.
I checked and it all worked, able to login, configure viewing and posting, etc.
I followed the page mentioned by podz, not the old upgrade page.
I edited wp-config-sample.php and changed its name to wp-config.php
added the info below
define('DB_NAME', 'drivein_wrdp6'); // The name of the database
define('DB_USER', 'drivein_wrdp6'); // Your MySQL username
define('DB_PASSWORD', 'leavingthisout'); // ...and password
define('DB_HOST', 'localhost'); // 99% chance you won't need to change this value
and went to wp-admin/upgrade.php
Says it cannot connect to host.
I double checked by compariing it to my other wp-config.php files for my other blogs.
It is the same except for different users and the password is different. They have 'localhost' as well and they work.
I did try in more than one browser to make sure the cached 'cannot connect' page wasn't coming up that way.
Any suggestions ?
edit: nothing in the database. This is all a brand new install.