I think you've moved the bug I've had 3 posts today (just regular forum posts) that resulted in a white screen and no response.. I've opened another window to verify that the post actually went (They all did). I've also noticed several double posts in forum threads recently... Happy Holidays!
I'm not sure if it's related, but I've also noticed that when editing some Wiki pages, you also get redirected to a blank page after saving the edit. The changes take, but no redirect back to the page.