i created a thread under my account 'ferguslogic' about t-sql in the tech off area and it disappeared too.
Heres how i made it disappear
1) i created the thread and it showed up
2) then i decided i needed to change something, i clicked edit and changed some text and the thread just completely disappeared
We've fixed this bug in dev and will be publishing sometime in the next couple hours. I will then go back and "fix" all the threads that have disappeared (it's a simple data problem I can easily fix). Your thread will be back shortly.