I worked on the forums last night but there are still two tables that are very unhappy. My understanding is at this point (based on the error codes) it's up to our host (Yahoo) to correct the issue. It's not something I can do on my end apparently. I sent them an email last night but haven't heard anything yet.
I've spent most of today exploring other hosting options. I have a moderately recent local backup of our forums, so I should be able to restore them into a new host's MySQL.
I'm sorry for the inconvienence this is causing everyone. The whole point of the new forums was to not have to deal with interruptions, etc.
If something comes up that you urgently need to speak to the officers about, there's a nice "Contact" link at the very bottom of this page. I check that email address very often.
Again, I'm sorry about all this. I'm working to fix things as fast as I can.
-Valyre