From Jeff's post:
Due to a failed software upgrade initiated by our hosting provider, in combination with a hardware failure in the backup system, we had to restore the forums from backup and currently have only been able to restore posts as of 1:10AM on Friday, August 31st.
We are working on retrieving additional posts, and have blocked new posts during the interim so that they don't interfere with the restore process. You can read posts, but you cannot reply or create new threads.
Thank you for your patience and please accept my apologies for the lost posts from today. We are working to restore as much as we can, as quickly as possible.
- Jeff

