Upgrading to MT3 worked pretty well overall.
However, I did have one problem. The mt-upgrade30.cgi script appears to contain an error (on line 114) which causes it to error out after doing some (but not all) of the necessary postgres schema changes.
I manually completed the rest of the changes and it appears to be working.
However, 'alter table mt_author drop constraint mt_author_author_name_key' should probably be changed to 'drop index mt_author_name_key' in the mt-upgrade30.cgi script on line 114 if one is to expect it to work with postgres.
