OK I finally figured it out. I had changed the root password when I did this upgrade. I had to manually edit the includes/config.inc.php to have that new password and it was set.
I might recommend a better error for that issue going forward.
I am now:
now on PHP 5.4.9
Now on MySQL 5.5.28
Now on UBB 7.5.7
and it seems to be working fine.
Now to install FastCGI.