Yeah, the bump helped.
See, here's the thing. You can post the actual thread title and then your post when making a new thread, so that vBulletin posts the title of the thread in blue out in the forums for others to see without actually clicking on it. The first line in bold print in your post is also the thread. But after 120 seconds, what happens is the title of the thread in blue that is visible in the forums cannot be changed except by a mod. You can, however, change the first line in bold in your post by going to your edit button and editing the title of the thread there, though the visible title of the thread in blue lettering will not change. Not sure if that answers you question fully.