1) Put up ONE thread for "New Site Bugs / Missing Functionality". Have the TSN Board moderators limit posts to that thread to Bugs and Functionality issues ONLY (mods delete complaining/opinions/wishlist posts). You shouldn't need to have to read through all threads and posts to get useful feedback.
2) Post a daily update to that thread in the first post with items that are resolved. That will keep the masses updated on progress.
3) DO NOT BOTHER READING ANY OTHER OF THE THREADS! It will only add to the stress levels that you already are dealing with. It has to be disheartening to read all of the negativity when you are still grinding out a go live.
4) Keep your chin up, a LOT of us here completely support the migration.