If you're something unusual when you look at the topic board now, it looks like Boss just added a great new vBulletin feature called "Live Topic".
What this does, is if there has been a post in a thread within the past 5 minutes, the topic is considered "Live". If you viewing that thread and it's "Live" and somebody posts something while you are reading it, you don't have to refresh. It will automatically refresh without you losing your spot and show the new post... It will give you a warning in the thread at the bottom of the screen that a new post has been submitted.