I’ve just upgraded to Vista. Apart from the random crashes (proper crashes, mind you – power off, no bluescreen) when you’re doing something intensive, the only problem is the moving of your documents.
Helpful error message in phpMyAdmin:
Cannot start session without errors, please check errors given in your PHP and/or webserver log file and configure your PHP installation properly
To get PHP to work again, you have to edit php.ini and replace references to your Documents and Settings folder (DOCUME~1 or similar) with the new Users folder (better name, should have done it before though, MS, tsk tsk).
And since your Local Settings don’t seem to work, you’ll have to lay out your own directories underneath.