You KILLED about 100,000 great Google Links to useful forums. You just made it very difficult for anyone to find useful info when searching for help with problems. You should have considered the Google effect.
Now, If I missed something let me know, but I don’t see how you even considered the Search Engine effect on your move.
I really think you should have moved the old forums to forums_archive then redirected all traffic to the original forums with a permanent redirect (htaccess).
Then create your new forums with support_forums or some other useful name. This would save you thousands and thousand of man hours on support.
Just trying to help.
Brad